If you close Firefox, then start Firefox in Safe Mode, does the problem still occur? To start in Safe Mode, go to Help > Restart with Add-ons Disabled.

If the problem does not occur in Safe Mode, then you can disable your extensions one-by-one until you find out which one is causing the problem. See Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems.

Thanks for your reply. The problem still occurs in Safe Mode. I also walked through all of the steps in Troubleshooting extensions and themes & could not find a solution. Any other advice? Thanks again.

Let's try something simple: Try clearing your cache and cookies.

1. Open the Tools menu, then select Clear Recent History.
2. In the Time Range to clear drop-down, select Everything.
3. Click the arrow next to Details to display the list of items that can be cleared.
4. Select both Cookies and Cache.
5. Click Clear Now.

Unfortunately this solution also didn't work. It's odd. I've got another Mac running the same version of Firefox & it can see and access the FCK functionality within the same CMS just fine. Also, my Dell is OK with it using IE.

Can it be a setting on my laptop rather than in Firefox? I'm also not able to see/access the FCK functionality on the same machine when using Safari 5.0.5.

Thanks.

From the searching I've done, people have reported that it works in a new OS account, or reinstalling from scratch. To me, that indicates that the problem is somewhere in the profile folder. For info on Firefox profiles, see Profiles - Where Firefox stores your bookmarks, passwords and other user data.

One thing you could do is create a new profile, then use Sync to migrate your data.

With a little more troubleshooting, we could find out the file in your profile folder that is causing the problem, which would be nice for anyone else experiencing the same problem. If you want to keep going, use the instructions at Recover important data from an old profile to move files one-by-one.