About 2 hours ago the usual firefox 3 update window appeared and I responded by clicking on the restart now button. Then followed an invitation to firefox 4 but after closing that, every time I tried to open firefox the web page for qwest appeared. I could still find other sites only if qwest was left open. I solved the problem by going to preferences for start page and found "Q" had been inserted. I chose the default setting option after deleting the "Q" and all is now back to normal. Is this a security risk?