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firefox won't load after update. Missing xul.dll

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  • Last reply by cor-el

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I run windows vista ultimate and after running auto update firefox wont load. Error message says missing xul.dll Have to reload the program again. It has only happened after the last 2 auto updates. Have been using firefox for 4 years without prior update problems.

I run windows vista ultimate and after running auto update firefox wont load. Error message says missing xul.dll Have to reload the program again. It has only happened after the last 2 auto updates. Have been using firefox for 4 years without prior update problems.

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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.

Don't remove personal data when uninstalling.

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.

You can skip the step to create a new profile, that is not necessary for this issue.

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


Do a malware check with a few malware scan programs.
You need to use all programs because each detects different malware.
Make sure that you update each program to get the latest version of the database before doing a scan.

See also "Spyware on Windows": http://kb.mozillazine.org/Popups_not_blocked and What to do when searches take you to the wrong search website