Xul.dll is a file used by the FireFox web browser to control the Internet browsing speed on your system. This file has been an integral part of the FireFox browser for several years, but is also one of the main causes of errors for this system. The good news is that you can fix this error pretty easily, by repairing the various problems which cause it to show.
The error that normally appears due to Xul.dll includes:
Firefox.exe – Bad Image
C:Program Filesmozilla Firefoxxul.dll is either not designed to run on WINDOWS or it contains an error. Try installing program again.
This error is normally caused by the xul.dll file either being outdated (incompatible with your current version of FireFox), or it is corrupt & unreadable. The first thing you should do to repair this issue is to reinstall the Firefox web browser in its entirety. This can be done by totally uninstalling the browser from your computer and then reinstalling it. This should place a fresh version of xul.dll on your PC, allowing Firefox to read the files it needs to run, fixing the error.
Reinstalling FireFox is easy, but it might not always work. If you try doing this and find it does not work, then it’s recommended that you manually replace the file on your PC. You can download Xul.dll from many Internet sites, and then put it into the FireFox folder on your PC. This will replace the file on your system and allow your computer to read the file it requires to run.
After doing this, you should then look to clean out the “registry” of your PC. Cleaning out the registry is an essential part of maintaining the Windows system, as it’s a central database for all the settings, files and options for your computer. Unfortunately, the registry is also one of the main reasons why Windows will run slowly & with various errors… as it’s continually being saved incorrectly. This causes your computer to take longer to read the files it needs from this database, slowing it down & causing errors. To fix this, you should use a ‘registry cleaner’ to repair any of the errors that are inside the registry of your PC, which should prevent the xul.dll error from appearing again.