The Best Free Software Unlocker (© All Computer Studies)

If you’ve ever been unable to delete a file in Windows, and can’t figure out what program’s using it, Unlocker is the solution. Have you ever seen these Windows error messages?

Cannot delete folder: It is being used by another person or program.
Cannot delete file: Access is denied.
There has been a sharing violation.
The source or destination file may be in use.
The file is in use by another program or user.

Make sure the disk is not full or write-protected and that the file is not currently in use.
Unlocker can help! Simply right-click the folder or file and select Unlocker. If the folder or file is locked, a window listing of lockers will appear. Simply click Unlock All and you are done!

PC Troubleshooting Tips Why is My PC Crashing? (© All Computer Studies)

Nothing can put a damper on productivity quite like a computer that crashes on a regular basis. Sometimes, a crash is preceded by the dreaded “blue screen of death” or another warning; other times, a computer simply shuts off without any warning at all. In either case, the end result is a whole lot of frustration, aggravation and lost work. If your computer has been crashing frequently, you’d probably like to put an end to it. Unfortunately, getting to the bottom of things if often easier said than done. The following tips about improving your computer’s performance, though, are excellent places to begin.

Possibility #1: Corrupted System Registry Files

Every Windows-based PC has something called a Windows registry. The registry contains several files that are integral to the performance and operation of your computer. Over time, some of those files can become corrupted, be misplaced or get lost altogether. When that happens, the system registry becomes compromised – and frequent crashes are all-too-common symptoms. The best way to rule this possibility in or out is by running a Windows registry cleaning program. Such programs scan your Windows registry for problems then automatically make repairs. If you run a registry cleaner and the crashes persist, they are probably being caused by a different issue.

Possibility #2: Disorganized Files

Windows operating systems handle file organization in a way that is not very intuitive. Basically, they break files up and fit them into gaps in the computer’s memory. As time goes by, these disorganized files can prompt frequent crashes. Luckily, a great optimization solution is built right into Windows-based PCs: the disk de-fragmentation utility. Although its location on a computer varies, you can generally locate it within the System and Security section inside the Control Panel. By running a defray once every few months, you may be able to keep those pesky computer crashes at bay.

Possibility #3: Malicious Software

Malicious software can take many different forms. Sometimes, it’s a virus that is accidentally unleashed after opening a strange email; other times, its aware that tags along with other information that is automatically downloaded from a website. Whatever type it is, there’s no question that malicious software can wreak havoc on a computer’s performance. Happily, there are many topnotch programs out there that regularly scan your computer for the presence of such problems – and that help guard against them, too. Buy one, install it and use it regularly; your crash issues may come to an end.

Possibility #4: Too Little Available Memory

When you buy a new computer, it feels like there’s no end to the amount of memory that it has. Of course, this is not true at all. As never-ending as the available memory on your PC may initially seem, the fact is that it can be depleted with incredible speed. You can find out for sure by checking the information within “My Computer.” If it appears that your available memory is low, you can use a PC cleanup program to remove unnecessary files; such programs remove things like temporary Internet files and other file debris that can suck away much-needed memory.

Possibility #5: Overheating

If you’ve run through all of the preceding possibilities and continue experiencing frequent crashes, a hardware issue could be to blame. An easy one to rule out is overheating. A computer’s CPU, or central processing unit, includes a fan that is designed to keep it running cool. Sometimes, the fan wears down and doesn’t work as efficiently; other times, it’s just not able to handle the work that your computer has to do. In either case, buying a bigger, better fan isn’t very expensive. If it puts an end to your PC crashing problem, it will have been more than worth it.

Don’t Put Up with Frequent Crashes!

As discussed, frequent computer crashes can be triggered by a wide variety of issues. Luckily, many of these issues are relatively easy to remedy. Work your way through the preceding list; chances are, you’ll be able to pinpoint the problem and put an effective cure to work. Nine times out of ten, a computer simply needs a little bit of routine maintenance to get it back on track again. In the future, keep these points in mind. Any time you buy a new computer, keep up with its basic maintenance right from the get-go. By doing that, you could avoid “blue screen of death” and crashing problems altogether – and that’s something that you’re bound to appreciate!

How to Back Up to your system? (© All Computer Studies)

There are many steps to save data with backup regularly.

Back up regularly your data. It is important factor for you to get backup your files and folder on a regular basis. Because in this global network a computer can crash, a virus, or a hard drive failure can wipe out everything. Don’t make this mistake, It depend upon you and your data importance but better technique is that back up everything at least once a week. But if you use your computer daily, it is best to back up important files daily and other data weekly.

Keep several backup copies of same backup. Never back up over a previous backup copy, always try to keep several copies over time so that if one time one back create problem you can user others.. Remember, a problem that is backed up will remain a problem when restored!

Easy way for backup using Be selective method. You don’t have to do a total system backup of your system over time, If your are doing so, you are wasting your time. Just back up your important files, folder and photos. Backing up the entire hard drive is time-consuming, not practical, and should not be done. A backup of specific data files is the way to go. But a best technique is that first install your all computer program and system drivers then do a backup using any third party software (cloning software) like Norton ghost or others of your C drive once, this backup will help you to restore your all computer program in 15 min in case of any problem and do important data backup daily or weekly.

How To Remove Bad Sector From Hard Disk (© All Computer Studies)

How To Remove Bad Sector

What Is a “Bad Sector”?
A bad sector, also known as a “surface defect”, is simply a sector on a computer’s disk drive that is physically damaged and therefore unable to be read. Usually, it is detected by the SCANDISK or CHKDSK utilities software that your operating system is equipped with.

When SCANDISK or CHKDSK find the bad sectors on your drive, they mark them so that the operating system will skip them in the future. This is known as standard disk repair.

Fixing Bad Sectors
Many PC users may come across bad sectors on their computers and not know how to fix them. Fortunately, a bad sector is not a lost sector – there is a way to save them. Once the bad sector is marked, the disk controller will remap the logical sector to a different area on the hard drive.

Since the drive has many spare sectors, the only reason the operating system would detect a bad sector would be if the surface of the disk drive was failing.

If this happens, it means the drive has run out of spare sectors and can no longer remap bad ones. This is very bad news for your operating system.

Common Symptoms
There are several common symptoms of bad sectors. One is the system blue screen. This is when your monitor screen suddenly turns blue during the middle of an operation. Often, this is because your system is unable to read a sector.

Another symptom is constant system freezes. This occurs because the operating system is unable to access the sector information it needs to load a page or open a file. Other symptoms include: “drive not formatted” error, “drive or device not found”, or “operating system not found”.

All of these error messages are signs that your computer system’s registry and memory are corrupted and need a fix.

Bad Sector Dangers
If system structures like the FAT are affected by bad sectors, it could cause your computer to freeze or even crash. That is where RegCure comes in.

RegCure’s software addresses sectors below the the file system, enabling it to detect the bad sectors that SCANDISK and CHKDSK cannot reach.

The advantage is that the disk management system can then go back to reallocating spare sectors where they are needed.

Connect Two Computers Using A Crossover Cable (© All Computer Studies)

Ever needed to connect two computers together without going through a wireless network? I’ve previously written about how to connect two computers wirelessly using an ad-hoc wireless network, but it’s not as fast as being directly connected.

If your computer are on a wired network, you can network two computers and then share files and folders, but it’s a lot of work! A crossover cable is another way to connect two computers and transfer data.

In order for this setup to work, there are a few things you need to make sure are setup or configured properly. I will try to go through all the different steps in this article.

Step 1 – Configure IP Addresses

Usually, if you are using a crossover cable to connect two computers, the computers are not connected to a LAN network. In this case, you will need to configure static IP addresses for each computer.

You have to make sure that both computers have IP addresses that are on the same subnet. For example, if you give one computer an IP address of 192.168.0.1, then you should give the second computer an IP of 192.168.0.2.

If you used the above IP addresses, you should use a subnet mask of 255.255.255.0. If you use an incorrect subnet mask, the connection will not work.

Lastly, the value for the default gateway should be the same on both machines. You can pick which IP address you want to use, but use it on both computers for the default gateway. Below is how my setup looks for one computer:

Step 2 – Crossover Cable

The second thing you need to verify is that you actually have a proper crossover cable. Basically, there are a few different types of crossover cables, but it’s best to get the standard crossover cable where the green and orange pairs are swapped and the brown and blue pairs stay in the same position.

The only pins that need to be crossed are 1,3 and 2,6. So just check your cable on both end and make sure it matches the diagram.

Step 3 – Local User Accounts

If you’re having problems accessing files both ways, you may have to create a user account on each computer that has the same name and same password. This helps get past any kind of Access is Denied errors that may pop up.

Make sure the accounts are administrator accounts also! It’s best to create a new account rather than rename a current account.

Step 4 – Disable Firewalls

Finally, you should disable the firewall on both computers to ensure that none of the file sharing ports are being blocked. You can do this by going to Control Panel and then Windows Firewall. Click on Off.

That’s about it! If you follow all these steps, each computer should be able to access the other properly. If you are having problems, post a comment here and I will try to help! Enjoy!

What is Computer Network? (© All Computer Studies)

Two or more computers connected together through a communication media form a computer network.
The computers are connected in a network to exchange information and data. The computers connected in a network can also use resources of other computers.

Computer Network Components

There are different components of a network. Following are the basic components of network.

1. Server:

Powerful computers that provides services to the other computers on the network.

2. Client:

Computer that uses the services that a server provides. The client is less powerful than server.

3. Media:

A physical connection between the devices on a network.

4. Network Adopter:

Network adopter or network interface card (NIC) is a circuit board with the components necessary for sending and receiving data. It is plugged into one of the available slots on the Personal Computer and transmission cable is attached to the connector on the Network Interface Card.

5. Resources:

Any thing available to a client on the network is considered a resource .Printers, data, fax devices and other network devices and information are resources.

6. User:

Any person that uses a client to access resources on the network.

8. Protocols:

These are written rules used for communications. They are the languages that computers use to talk to each other on a network.

Power Supply Unit (Hardware L#7) (© All Computer Studies)

The Power Supply Unit or PSU for short, converts Alternating Current that comes from the electricity mains into the Direct Current that is required by a computer’s hardware components. Because the PSU is responsible for powering your entire computer system it is a very important piece of hardware. However, buyers often don’t give the PSU the consideration it deserves.

The PSU is rated according to the Watts of power it can output. For example a 300W PSU. PSUs also have an efficiency rating that determines how good they are at converting AC to DC without wasting energy.

Power supply units and efficiency

Computer Power Supply Units or PSUs convert mains Alternating Current (AC) to the Direct Current (DC) required by computer parts. Power supplies are typically rated in watts of power they can reliably supply to a computer. But these PSUs aren’t 100% efficient at their job. Some power is lost during the conversion from AC to DC. How efficient they are at their job determines how much electricity your computer uses and that is reflected in your monthly electricity bill.

A typical generic PSU will have an efficiency rating of 60%. That is 40% of the power it consumes will be wasted.

There is a certification system for branded power supply units called 80+. This requires power supply units to be at least 80% efficient. There are different levels of 80+ certifications. They go from just 80+ standard to bronze, silver, gold and platinum. The higher levels are for more efficient power supply units with 80+ platinum being 90% efficient.

Saving power

Lets take a look at how a typical generic 500W power supply unit compares to a 80% efficient branded one when operating at full load. That is when it is supplying 500W of power to the computer system:

60% efficient PSU = 500/60 x 100= 833W

80% efficient PSU = 500/80 x 100= 625W

So by using a more efficient PSU you save about 200W per hour or 1600W (1.6KW) per day if your system runs 8 hours a day at full load. Electricity prices are measured in units of 1000W consumed in an hour or 1KW. At the time of writing each unit of electricity costs between Rs. 7-10 in Pakistan. So you can now calculate your savings from using a more efficient PSU.

Of course in reality few computers use 500W all the time. Most modern computer system units with integrated graphics idle at 40-60W and use 80-120W under moderate load. So you also have too look at how efficient these PSUs are at supplying less than the rated power output. That is how efficient are they at supplying 20% or 40% of the rated power wattage? Can they also achieve 80% efficiency at that load level? The beauty of the 80+ efficiency rating is that it requires power supplies to be 80% efficient at 20%, 50% and 100% of the rated load.

But when your computer is consuming little electricity in the first place the savings to be had from a more efficient PSU are much less. So little in fact that the monetary savings don’t make them worth the extra expense in the short term. In the long term the efficient PSUs may save you money depending on how much power your computer consumes, how many hours a day you use it and the price of electricity.

Wasted power

Now what happens to the power that is wasted during the conversion from AC to DC? That power is wasted in the form of heat given out by the PSU. The less efficient the PSU, the more heat it generates. In the very hot Pakistani weather you might want to buy an efficient power supply unit just to help keep your room cool!

Optical Drives (Hardware L#6) (© All Computer Studies)

Optical Drives are used to read and/or write to removable optical disks like CD-ROMs and DVD-ROMS. Optical drives work by using lasers to read microscopic pits on the surface of optical disks. These pits and their absence represent the binary states of 1 and 0.

Optical drives are slower than hard disk drives or SSDs and they are of smaller capacity as well. Optical disks are non-volatile, permanent storage media.

The different types of optical drives are:

•     CD ROM Drive : Reads CDs.
•     CD Writer: Reads and writes or “burns” CDs.
•     DVD ROM Drive: Reads CDs and DVDs.
•     DVD Writer: Reads and writes CDs and DVDs.
•     Blu ray drive: Reads blu ray disks, CDs and DVDs.
•     Blu Ray burner: Burns and reads blu ray, DVDs and CDs.

Before software distribution via the Internet became common place, an optical disk was usually the only way you could install software on a computer system. So optical drives used to be very popular but are no longer as important as they once were.

Hard Disk Drive (Hardware L#5) (© All Computer Studies)

A Hard disk drive is a permanent storage device used in a computer system. A HardDisk Drive or HDD consists of rotating platters of magnetic disks that store large amounts of data in a non-volatile or permanent state. That means that HDD data does not disappear when you turn off the computer.

Hard Disks are slower than main memory but faster than Optical drives. HDDs usually store the operating system and application software of a computer.

HDD capacity is measured in gigabytes or billions of bytes and in terabytes or trillions of bytes. The performance of an HDD is determined by a variety of factors including:

Revolutions Per Minute (RPM): How fast the platters spin per minute. The higher this number the faster a hard disk is. At the time of writing a 7200RPM hard disk would be the standard for desktop computers.

Cache: The amount of cache memory on-board the drive. The cache memory is used to store frequently accessed data. It is faster to deliver data from the cache than from the platters themselves.

 Access time: Access time is the amount of time it takes to find and retrieve data from the hard disk. The lower the access time the faster the hard disk functions. Access time of 12-13ms is the norm for desktop hard drives at the time of writing.

Solid State Drive

A relatively recent invention, Solid State Drives (SSD) are a fast permanent storage device. SSDs use flash memory to store data quickly. SSDs are much faster than hard disk drives but are slower than main memory. SSDs are also more expensive than hard disk drives on cost per-gigabyte basis.

Because of their high cost SSDs aren’t as common as Hard disk drives. But prices are dropping fast and that should increase SSD adoption rates. SSDs usually come in 2.5″ form factor that requires the use of an adapter to get them to fit in a computer case. Some computer cases come with adapters built into them for SSDs.

SSDs do not have any moving parts in them so they make no noise whatsoever. This is another differentiating factor that separates SSDs with HDDs.

Random Access Memory [RAM] (Hardware L#4) (© All Computer Studies)

Random Access Memory or RAM is high speed volatile storage space in a computer system. RAM is one of the fastest storage areas in a computer system. RAM is also known as main memory or just memory.

On modern computers RAM usually comes in the form of Dynamic Random Access Memory or DRAM. DRAM is RAM that has to be regularly refreshed by the memory controller. DRAM is cheaper than the alternative memory called Static RAM but is also slower than SRAM.

Generally speaking, the more RAM you have in your PC the faster your PC operates. RAM is used to store running programs and associated data. It is also used to cache access to slower storage mediums like hard disk drives.

There are different standards for DRAM. As the technology evolves older standards are replaced with newer and faster ones. Some of the standards of DRAM are:

SDRAM

DDR

DDR2

DDR3

RAM comes in the form of a module (pictured on the left) referred to as a Single Inline Memory Module (SIMM) or nowadays Dual Inline Memory Module (DIMM). DIMMs are inserted into a socket on the motherboard.

Central Processing Unit [CPU] (Hardware L#3) (© All Computer Studies)

The Central Processing Unit or CPU is the main arithmetic and logic processing unit in a computer system. The CPU carries out all the instructions you give to your computer. In modern computer systems the CPU is a microprocessor chip and its installed in a socket on the motherboard. The CPU communicates with the rest of the computer system via the bus on the motherboard.

The CPU consists of different parts such as:

Control Unit: The control unit directs the fetching, decoding, execution and storage of results of instructions in a CPU.

Arithmetic Logic Unit (ALU): The aforementioned ALU performs the arithmetic and logic functions in a CPU.

Registers: Registers are high speed storage areas that store data related to program code that is being executed.

Cache: Cache consists on of on-die SRAM or high speed memory used to improve access times to main memory by pre-fetching data needed by the CPU.

Floating Point Unit: The FPU is used to perform complex calculation involving fractional numbers.

Computer Motherboard (Hardware L#2) (© All Computer Studies)

The motherboard is the main circuit board in a computer system. All the other parts of a computer plug into the motherboard. The motherboard is also called a mainboard or system board.

The motherboard has a socket for the CPU, RAM modules and add on cards. In the above picture the CPU socket is the large one in the center right. The RAM sockets are the two longish light blue ones in the bottom of the picture.

The motherboard also has sockets into which you plug in your permanent storage devices like hard disk drive and solid state drive. Peripheral devices also plug into the motherboard. You can see the sockets for the peripheral devices at the top right of the picture.

The most important part of the motherboard is its chipset. The chipset determines which CPUs and addon devices the motherboard supports.

The motherboard is the foundation of your computer system. That is also why it’s called the motherboard. You have lots of circuit boards but only one motherboard.

Computer Case (Hardware L#1) (© All Computer Studies)

The computer case or system unit is a big box that usually sits in a dusty corner on the floor and no one ever pays any attention to it. In fact it’s ignored so much that people have even forgotten what it’s called! They call it by other names like “CPU”. Now if you want to learn about computer hardware you will have to learn to call things by their correct names. So lesson number 1 is that a computer case is not a CPU. So what is a computer case? Take a look at the picture below:

The computer case houses the main hardware components in your computer system. Without it you would have no computer.

As you can see from the picture above there are two main types of computer cases. The tower variety on the right is taller than it’s wide. And then there is the desktop computer case on the left. Desktop cases are no longer in fashion because they take up desk space. Tower cases, on the other hand, can be tucked out of sight underneath your desk so they are more in fashion.

But what’s really important is the stuff that’s inside the computer case:

What Is Operating System? (© All Computer Studies)

An operating system or OS is a software program that enables the computer hardware to communicate and operate with the computer software. Without a computer operating system, a computer and software programs would be useless. In the picture to the right, is an example of Microsoft Windows XP, a popular operating system and what the box may look like if you were to visit a local retail store to purchase it.

Examples of computer operating systems

Microsoft Windows 7 – PC and IBM compatible operating system. Microsoft Windows is the most commonly found and used operating system.
Apple MacOS – Apple computer operating system. The only Apple computer operating system.
Ubuntu Linux – A popular variant of Linux used with PC and IBM compatible computers.
Google Android – operating system used with Android compatible phones.
iOS – Operating system used with the Apple iPhone.