After i use and apply changes i made in the WINDOWS costumization tools inside the system mechanic, the computer boots. after the window started, there was nothing appear except for the background. No taskbar, no desktop icons and i cannot right click.. I can only explore windows using TASK manager N i open system mechanic using it. After opening system mechanic, I click the button help and it states that if i want to UNDO changes made i must undo it using safetyNet.. But after undo the changes.. nothing happens... I have tried system restore, open windows in safe mode, but the problem is still... I had open the control panel and there are 2 network connection icon, one is for network connection and when i click the other one an error message appear telling me that 'null' file is missing, when i click the startmenu and taskbar icon, nothing happens... Well, for your information i was using Windows XP sp2, hp compaq presario v3000Just to clarify... you were using the software called System Mechanic correct?

Try letting windows repair any damaged or missing system files by ruining this command:
sfc /scannow

You can run it from the task manager by CHOOSING File --> New Task.
You will need your XP install disc.Another thing to try:

In Task Manager, on the File menu, click New Task (Run).
Type:
cmd
Hit ENTER.
Rename the Shdocvw.dll file by typing:
ren shdocvw.dll shdocvw.old (<----- watch for spaces)
Restart the computer.Isn't this the 3rd or 4th issue this week related to System Mechanic ? ?I don't know why that System Mechanic is so popular?
Is it because they advertise it as some kind of miracle tool?