Hi, do other browsers work? If so, try performing a Clean reinstall. This means you remove your Firefox program files and then reinstall Firefox - not the same as a simple reinstall. This process does not remove your Firefox profile data (such as bookmarks and passwords), since that information is stored in a different location.

To do a clean reinstall of Firefox, please follow these steps: Note: You might want to print these steps or view them in another browser.

1. Download the latest Desktop version of Firefox from mozilla.org (or choose the download for your operating system and language from this page) and save the setup file to your computer.
2. After the download finishes, close all Firefox windows (or open the Firefox menu and click the close button ).
3. Delete the Firefox installation folder, which is located in one of these locations, by default:
   • Windows:
     • C:\Program Files\Mozilla Firefox
     • C:\Program Files (x86)\Mozilla Firefox
   • Mac: Delete Firefox from the Applications folder.
   • Linux: If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it - see Install Firefox on Linux. If you downloaded and installed the binary package from the Firefox download page, simply remove the folder firefox in your home directory.
4. Now, go ahead and reinstall Firefox:
   1. Double-click the downloaded installation file and go through the steps of the installation wizard.
   2. Once the wizard is finished, choose to directly open Firefox after clicking the Finish button.

More information about reinstalling Firefox can be found here.

WARNING: Do not use a third party uninstaller as part of this process. Doing so could permanently delete your Firefox profile data, including but not limited to, extensions, cache, cookies, bookmarks, personal settings and saved passwords. These cannot be easily recovered unless they have been backed up to an external device! See Back up and restore information in Firefox profiles.

Sometimes a problem with Firefox may be a result of malware installed on your computer, that you may not be aware of.

You can try these free programs to scan for malware, which work with your existing antivirus software:

• Microsoft Safety Scanner
• MalwareBytes' Anti-Malware
• Anti-Rootkit Utility - TDSSKiller (for more info, see this alternate TDSSKiller download page)
• AdwCleaner (for more info, see this alternate AdwCleaner download page)
• Hitman Pro
• ESET Online Scanner

Note that not all removal programs will detect all malware, so you may need to run several or all of them.

Further information can be found in the Troubleshoot Firefox issues caused by malware article.

Did this fix your problems? Please report back to us! Thank you.

Thanks.

Edge and Chrome both load but as I have Firefox as the default I don't know whether the links from my Outlook messages or Word files would open on them either.

I use Windows Defender (as default AV prog) and Malwarebytes on a weekly manual basis already and when the Zeus page arrived in a 'drive by' attack, neither picked it up when I scanned from both while the page was screaming at me. MWB Support later told me that as it wasn't a virus per se and just a page hi jack , their program wouldn't recognise it as such. (that seems strange to me but there you go)

I did in fact re install Firefox as mentioned on 27th in the same way you call 'Clean' where I cleared the old install and run programs from the C: Program before re installing the new version.

I've just loaded the Windows Safety Scanner following your recommendation and run a scan which showed nothing but I'm wary of downloading a Kaspersky or the other two.

Before I try once again to uninstall and reinstall as your advice above, are you sure the problem isn't simply a setting problem with the new version of Firefox or an Add On or Plug In error in the latest Mozilla version that I downloaded on the 27th? I haven't downloaded anything else by the way from the Firefox options since then or any other software that I'm aware of.

Alternatively could the previous installed MS programs be not letting me access the new version of Firefox for some reason?

Oh, and I see there's a 'Refresh' option as well somewhere on the Mozilla site. Is that worth trying first? If so can you give me the link as I didn't keep it?

Your only plugin seems to be Flash, and there aren't any self installed add-ons showing, but it won't do any harm to try in Safe Mode - hold down Shift when you start Firefox to start in Safe Mode. More - Diagnose Firefox issues using Troubleshoot Mode

Refresh may work, but can very occasionally cause issues of its own, so to be on the safe side, before you do it, I would backup your bookmarks: Open bookmarks > Show All Bookmarks > Import and Backup > Backup. Or, Export Bookmarks to HTML, and save them to somewhere convenient on your computer. Note that Backup will overwrite any existing bookmarks when you restore them. For extra safety, I'd suggest making both a Backup - which creates a JSON file, and an HTML file. You can instead backup all your data by copying your Profile, but this requires some technical expertise - Back up and restore information in Firefox profiles.

The Refresh feature (called "Reset" in older Firefox versions) can fix many issues by restoring Firefox to its factory default state while saving your bookmarks, history, passwords, cookies, and other essential information.

Note: When you use this feature, you will lose any extensions, toolbar customizations, and some preferences. See the Refresh Firefox - reset add-ons and settings article for more information.

To Refresh Firefox:

1. Open the Troubleshooting Information page using one of these methods:
   • Click the menu button , click help and select Troubleshooting Information. A new tab containing your troubleshooting information should open.
   • If you're unable to access the Help menu, type about:support in your address bar to bring up the Troubleshooting Information page.
2. At the top right corner of the page, you should see a button that says "Refresh Firefox" ("Reset Firefox" in older Firefox versions). Click on it.
3. Firefox will close. After the refresh process is completed, Firefox will show a window with the information that is imported.
4. Click Finish and Firefox will reopen.

Did this fix the problem? Please report back to us!

Thank you.

See also:

• https://support.microsoft.com/en-us/help/310049/hyperlinks-are-not-working-in-outlook

This issue can be a problem with the default browser settings where some registry keys are incorrect or corrupted. You can try to redo the default browser setting and temporarily set another browser as the default browser. If that doesn't help then try to uninstall and reinstall Firefox. When you are on Windows 10 then make sure to set another browser as the default browser before uninstalling Firefox.

• https://support.mozilla.org/en-US/kb/how-make-web-links-open-firefox-default
• https://support.mozilla.org/en-US/kb/setting-firefox-default-browser-does-not-work

Spent 4 hours online with MS support this morning via three different people. First two didn't seem to know much, third one said it was likely a corrupted Outlook. He ran me though whole process of making IE the default browser which I haven't used for 3 years (but didn't advise me to uninstall the firefox) which he said would get the hyperlinks working again. It didn't! Doesn't give me much confidence in MS. I've re set Firefox as default therfore.

Haven't tried refresh yet or safe mode start.

I use Office 2013 and I think problem is in there somewhere in that it's not recognizing the new version of Firefox I re installed after the Zeus problem.