I solved my own problem when I cleaned out the FirFox cache file. Hope this helps someone else.
A few weeks ago, I updated my favourite browser FireFox to ver 18.104.22.168 Up until this morning I've not had any problems but now when I try to get to my personal website I get the message - "Firefox can't find the file at /." This is the same message even if I use the IP address or if I try using an anonymous website. I've no problem using IE which eliminates XP's hidden host file.
I've tried a system restore to a date when everything worked but no luck.
I would prefer to find the problem as to trying to un-installing and reloading Firefox, although I'm not sure this would work. Any suggestion?