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Firefox 5.0 with WinXP(SP3) error at launch: "procedure entry point "JS_DefinePropertyById could not be located in js3250.dll"

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Downloaded and installed FFox 5.0 this morning. Running XP/SP3 with Zone Alarm Extreme Security firewall,etc. Having been using earlier versions (4.x) for a long time with no problems. Now when launching FF5 get error msg "procedure point JS_DefinePropertyById could not be located in... js3250.dll" and the firefox process keeps running (as seen in the Task Manager). What's going on??

Downloaded and installed FFox 5.0 this morning. Running XP/SP3 with Zone Alarm Extreme Security firewall,etc. Having been using earlier versions (4.x) for a long time with no problems. Now when launching FF5 get error msg "procedure point JS_DefinePropertyById could not be located in... js3250.dll" and the firefox process keeps running (as seen in the Task Manager). What's going on??

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Download a fresh Firefox copy and save the file to the desktop.

  • Uninstall your current Firefox version.
  • Do not remove personal data when you uninstall the current version.

Remove the Firefox program folder before installing that newly downloaded 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.

Your bookmarks and other profile data are stored elsewhere in the Firefox Profile Folder and won't be affected by a reinstall, but make sure that you do not select to remove personal data if you uninstall Firefox.

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>Uninstall the previous version of firefox >delete all the cache n browsing data >after uninstall go to system folder delete firefox folder >restart your system >and install firefox again(download firefox from mozilla site)