I have installed Internet Download Manager (IDM), I download any file using IDM when it is going to finish it always restart my Windows XP.
Please help me.....
I think you must have messed with Scheduler :
Tell me if it works :)
I didn't find the option to comment so I'm writing this as an answer. Can you provide some more details? I'll edit this answer when I get more details from you.
1) When it restarts what exactly do you see on your screen? Do you see the blue screen? Or some error dialog? Or is it a spontaneous restart (one second you are seeing the idm, next second you are seeing your bios)?
2) Have you tried downloading without the IDM? Does the restart happen with a normal download without the IDM?
3) Which version of Windows XP are you using? And much RAM do you have and what is the free disk space on your drive?
4) Which version of IDM are you using?
Right now I can only make a guess and I think it could be due to a malfunctioning RAM.