i have a windows 7 hp. a year after a bought it went to blue screen i have reintall windows. when i do it works but after a month or it happends again i have reinstall windows more than 7 times what can be the problem

Did you collect the information off the blue screen? The error numbers and any files mentioned would be where we would start to diagnose this issue. Always pop back and let us know the outcome - thanks
Might turn out to be best, as blue screens can be either hardware or software. Intermittent faults can often be a pig to find. EDIT:
I overlapped with post below, which is a good idea.
Another thought is to see if anything is mentioned in Events.Always pop back and let us know the outcome - thanks
the log might be found in c:/windows/minidump. if thats the case post a couple of lines,
:: mike
That is a lot of reinstalls in a short time. Unless you know that you are getting malware/root kits, I would suspect hardware, possibly a bad memory module or a bad hard drive. You can test your memory with Memtest (burn to CD and boot to it). You can test your hard drive with the hard drive manufacture's utility also burned to a bootable CD and booted to. Run the longest test on the hard drive and let Memtest run through all of its tests. In memtest, any errors can mean you need to replace the memory. On the hard drive test, minor errors can usually be repaired by the utility, but major ones or too many minor ones, will mean the drive will need replacing. If you get repaired errors on the hard drive, rerun the test after a month or so and if there are new errors, consider replacing it retroactively. You have to be a little bit crazy to keep you from going insane.
Agree with Fingers. Either you're repeatedly contracting malware or you have a hardware problem. Try F8 after the BIOS screen and see if you have a system diagnostic built in. Otherwise do as Fingers suggests. Also try a burn-in program.
