I have been having several problems with Firefox recently, the most prominent of which is my current inability to access the address bar or its drop down menu. When I click on either of these I get a firefox.exe message from Microsoft apologizing but indicating that firefox.exe has encountered an error and needs to close, offering a send/not send option. Another error message from Mozilla Quality Feedback Agent also makes the same offer. Reporting to either of these entities does not produce a response. I have also had other Firefox problems lately: getting stuck in a "do" loop and not being able to open the program, thereby necessitating shutdown/restart and going to an earlier system restore for a cure; and delays in completely loading the home page and subsequent linking from the any pages (with the same necessary cure). When I must shut down/restart from the do loop problem, before shutting down, I get a message indicating the absenceof a dll file for firefox.exe. I presume that restoring reloads that dll file, but why do my problems appear to continue?
I am running XP Pro on a Dell 8200 with up to date Norton virus definitions and scans, as well as the same on SpyBot and Ad-Aware. Is the solution to redownload Firefox, and if so, will I be able to keep all of my current Firefox preferences, e-mails, and bookmarks?

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