Verified answer

why doesn't it run? doesn't it give any report and if what does it say? or does it just not start up?

if you have a xp cd, then start ur computer and on the desktop,

click start button-run-

type "cmd". press enter.

in the command prompt type

sfc/scannow

and press enter. now it'll ask you to insert ur windows xp installation disk. do so. it will replace all the missing and corrupted system files.

nb: there may be chance for lossing user documents in c drive.

now most of the problems will be saved. also reinstall mozilla if it fails to start. also use a good antivirus/

Try system restore to an earlier point before you started having these problems.

If that fails, backup important files, format and reinstall.