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what does firefox.exe-application error mean? Firefox wont even open it just says this, and then click okay to terminate the problem.


When I go to open up Firefox, it does not open no matter what I try It just pops up this box that says Firefox.exe - application error. Then it says the Instruction at "0x798377a9" referenced memory at "0x798377a9". The memory could not be "written". Click on OK to termintate the program What does this mean? And why cant I use Firefox. I can still use internet explorer just fine.

User Agent

Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; InfoPath.1)

Additional System Details


  • User Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; InfoPath.1)

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10739 solutions 96651 answers

Do a clean reinstall and download a fresh Firefox copy from http://www.mozilla.com/firefox/all.html and save the file to the desktop. Uninstall your current Firefox version and remove the Firefox program folder before installing that copy of the Firefox installer. It is important to delete the Firefox program folder to remove all the files and make sure that there are no problems with files that were leftover after uninstalling.

..... See http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Clean_reinstall