I have a question, My brother in laws computer XP Pro is not a genuine copy of Windows. He bought it that way. It has worked fine up until the other day. You open the browser, AOL or IE6, it may stay up from a few seconds to a minute. Then an error pops up saying that it has to close. Digital Signature. Now, I went to check out his problem and get his documents off computer and it wont let me. errror. Would windows have some sort of time limit that the system will work right. He has had this CPU for about 4 years. Never a problem. I am thinking it may be a virus. He has no anti-virus on it. I am going to try to install Avira and CCleaner.