Deleting unwanted files from hard disc:
Dear friends this problem occurs only when you dont install files proprly in your system.It is difficult to delete those files which are not install proprly in your system.A simple procedure to delete or clean up unnecessary files form your system.Just follow the below steps to clean up your system.
Click on start>Go to accessories>System tools>and then click on Clean up.
In order to delete unnecessary files you have to do disc clean up.for this you have to follow the above steps.A small disc clean up tool is build internally in your system.Select c:\ drive to clean up and click on first tab as shown below “disc clean up”.It deletes all unnecessary,hidden and unwanted files from your system.
Disc clean up to perform any of the following below tasks to free up disc space on your hard disc:
-Empty Recycle Bin.
-Remove Windows temporary files.
-Remove unnecessary downloaded files programs.such as c,java applets,active x etc.
-Remove installed programs which you never use.For example after playing any game completely better you uninstall it.Why because games occupy huge space.
-A few windows programs which are optional which you never use.Better you delete those kind of programs.
You can clean those kind of files by below method.
- Click Start and click Run.In that type “cleanmgr” and then click “OK”.
In some cases disc clean up dosen’t work properly.especially when INDEX.DAT file is corrupted.

C:\WINDOWS\Prefetch:
This folder contains regularly used programs.Without any problem you can delete those files completely.Your system will start quicker after deleting those files from your system.The files in prefetch folder will generate automatically as soon as you restart your system.

C:\I386\
C:\Windows\Driver Cache\I386\
C:\Windows\ServicePackFiles\I386\
If you really want to save your disc space then delete the above files immediately. 1386 folder contains all setup files.If your system is working proporly then there is no need of above files.You can delete them.I am not responsible if your system does not work properly after deleting those files. ..My best tool is Active Eraser which deletes all unwanted files completely from your system.
Active-Eraser software mainly consists of 4 components:
1)Secure File Eraser.
2)hard Disc Drive Eraser.
3)Disc Wiper.
4)Internet Trace Eraser and Local Activities Cleaner.
Prefer to use this tool before defragmentation.

The below temporary files which you can remove completely from your system.I can assure that your system will be safe after deleting the below files.
C:\Documents and Settings\your username\Local Settings\Temp
C:\Documents and Settings\Default User\Local Settings\Temp
C:\Documents and Settings\LocalService\Local Settings\Temp
C:\WINDOWS\TEMP
C:\Documents and Settings\your username\Local Settings\Temporary Internet Files
C:\Documents and Settings\Default User\Local Settings\Temporary Internet Files
C:\Documents and Settings\LocalService\Local Settings\Temporary Internet Files
C:\Documents and Settings\your username\Local Settings\History
C:\Documents and Settings\Default User\Local Settings\History
C:\Documents and Settings\LocalService\Local Settings\History.

C:\PAGEFILE.SYS (Virtual memory) page files:
The page files are used only when your main memory has been used by running programs.For this more memory is needed.Page files are used temporary .So we can delete those files completely from our system.Disabling the pagefile is only a wise thing to do if the available memory exceeds 512 MB (the use of the pagefile depends on the demand for memory of the running applications). You can also move the pagefile to another (faster) partition (as suggested on the page Windows XP settings part I) to make a quicker system backup/recovery possible.

How to delete locked files:Some files cannot be delete by above procedures.Even by using Active-Eraser you cannot delete locked files.Because the file or folder is locked by specific process or method.You have to find which process is locking those files.After finding you have to stop the process.For this download Microsoft Process Explorer v11.4.The unique capabilities of Process Explorer make it useful for tracking down DLL-version problems or handle leaks, and provide insight into the way Windows and applications work.Another tool Unlocker which unlockes the file or folder from specific process and deletes those files.

Few disc cleaning softwares are shown below.
- Download Sreenit.exe.
- Download File Encryption.
- Download Disk Invistigator.
- Download Delete Doctor.