i booted knoppix from live cd and in that i was not able to copy any file to my pen drive and external hard disk
so i changed their mode to writable and also changed permission for user, owner and group all to read and modify content
so then i was able to copy file in knoppix
but the next time when i booted windows XP from my primary hard disk then it was behaving read only the error message shown is "access is denied" .. pls help me out how can i change my pen drive and external hard disk back to writable mode in XP..