Error Message:

For about three weeks now I have been getting an error message that reads:
"Windows cannot access the specified device, path, or file. You may not have the appropriate permission to access" This message comes up quite frequently when I try to go to many different things that I have never had trouble going to before. This just came up when I clicked on "Program Files\Messenger\msmsgs.exe ". Another problem that has recently shown up is to do with Internet Explorer. When I try to click on a widow or area of a website it immediately kicks me off of the internet. I have re-logged on only to have the same thing happen again. By the way--The message at the top of this thread about not having permission now happens anytime someone sends me a wav video in an email. I have to download it to my desktop before I can open it.
Any one with any solutions or ideas on how to over come these problems I am having, I would appreciate ar reply. I am running XP Professional and my email address is "Email address removed "
Thanks, Bob Johnson