Thank you friends for your suggestions I have formatted my c drive and re-installed windows I think I found a solution for my problem:) I still don't know reason for thhe problem.
Yes, my windows is original.I've booted it from the original disc. Opera , mozilla firefox , adobe reader, xampp are all open source.So they are genuine.
Hello,i am new to this community I use Windows 7 64-bit.I formatted c drive recently. I installed Mozilla firefox browser, which worked then. after rebooting system, it never worked. I also installed Opera and faced same problem .It also showed an error an closed. I managed browsing in Google...