xpinstall.enabled seems to be missing
I've tried to install an ad on, I get the message that it's downloaded ok & I need to restart FF I've done this but nothing has happened started about:config typed xpinstall.enabled as instructed.
xpinstall.enabled is not there ? what next?
Additional System Details
- NPRuntime Script Plug-in Library for Java(TM) Deploy
- Adobe PDF Plug-In For Firefox and Netscape "9.4.5"
- The QuickTime Plugin allows you to view a wide variety of multimedia content in Web pages. For more information, visit the QuickTime Web site.
- Shockwave Flash 10.2 r152
- Adobe Shockwave for Director Netscape plug-in, version 11.5
- Garmin Communicator Plug-In 18.104.22.168
- Next Generation Java Plug-in 1.6.0_26 for Mozilla browsers
- Office Authorization plug-in for NPAPI browsers
- The plug-in allows you to open and edit files using Microsoft Office applications
- Google Update
- User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:6.0) Gecko/20100101 Firefox/6.0
The pref xpinstall.enabled is only present if it doesn't have the default value true and if that setting is disabled then you would get as far as you were already getting by downloading the file.
Delete the files extensions.* (extensions.sqlite, extensions.ini, extensions.cache, extensions.rdf) and compatibility.ini in the Firefox profile folder to reset the extensions registry.
New files will be created when required.
See "Corrupt extension files":
If you see disabled, not compatible, extensions in "Tools > Add-ons > Extensions" then click the Tools button at the left side of the Search Bar (or click the "Find Updates" button in older Firefox versions) to do a compatibility check or see if there is an update.