The memory could not be written

After i change My Computer name, my machine (Windows XP Pro SP3) getting very very slow and hit below message when try to install some simple application and even hit the same error notepad.

"The instruction at "0×62e2cc0f" referenced memory at "000000000". The memory could not be written. "

Try to work around and suft here and there but not able to find any solution.

Finally System Restore work for me.

To use System Restore to restore Windows XP to a previous state, follow these steps:

1. Log on to Windows as Administrator.
2. Click Start, point to All Programs, point to Accessories, point to System Tools, and then click System Restore. System Restore starts.
3. On the Welcome to System Restore page, click Restore my computer to an earlier time (if it is not already selected), and then click Next.
4. On the Select a Restore Point page, click the most recent system restore point in the On this list, click a restore point list, and then click Next.
   Note A System Restore message may appear that lists configuration changes that System Restore will make. Click OK.
5. On the Confirm Restore Point Selection page, click Next. System Restore restores the previous Windows XP configuration, and then restarts the computer.
6. Log on to the computer as Administrator. The System Restore Restoration Complete page is displayed.
7. Click OK.

For more information, please visit http://support.microsoft.com/kb/306084