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The issue or problem is caused by system drive letter has change or a software has changed the default security provider without knowledge of users.

To resolve the issue, change the system drive letter to revert it back to original value, or match the new drive letter to the security provider. If the default security provider has been changed, reset the default security provider in Windows XP by deleting the relevant keys in the registry.

Reset the Default Security Provider in Windows XP
Start the computer. Press the F8 key during startup to start the computer in Safe mode.
Start Registry Editor (Regedt32.exe).
Delete the following registry keys in the Windows registry:HKEY_USERS\.DEFAULT\Software\Microsoft\Cryptography\Providers
HKEY_USERS\S-1-5-20\Software\Microsoft\Cryptography\Providers
Quit Registry Editor.
Restart the computer.

Match the Default Security Provider to New Drive Letter
Run Registry Editor (Regedit.exe).
Navigate to the following registry key:HKEY_LOCAL_MACHINE\Software\Microsoft\Cryptography\Defaults\Provider
You will see a few Provider key beneath the branch. In each Provider key, edit the Image Path value to match the new drive letter.
Exit Registry Editor.
Restart computer.

Reset the Drive Letter of the System Drive

Use Registry Editor to change the drive letter of the system drive back to its original value. Edit the following registry key to change the value of the system drive:

HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices

where \DosDevices\C: and other values presents the drive letters.

it it is xp the follow the following steps
When you start to shut down Windows XP, it has to quit, or "kill," any live
applications or processes that are currently running. So close all applications first.
However, some applications and processes are always running in the background.
You can reduce the amount of time that Windows XP waits for those applications and
processes to close before Windows XP kills them.
1. Open registry editor
2. Navigate to HKEY_USERS\.DEFAULT\Control Panel\Desktop. Set the
WaitToKillAppTimeout and set the value to 1000. Select the HungAppTimeout
\newline value and set it to 1000 as well.
3. Navigate to HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control.
Select the WaitToKillServiceTimeout value and set it to 10000.
4. Close the Registry Editor.


Memory Tweak
1. Start Registry Editor (Regedit.exe) and locate the following key in the registry:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SessionManager\
MemoryManagement\PrefetchParameters
2.On the EnablePrefetcher value, change the setting from 3 to 5 (decimal).
3. Close the registry editor and restart your computer

you need to upgrad your memory speed

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