Try this:
Type about:config into address bar, hit enter, Firefox would ask if you want to access the settings, say yes you know the risk.

When the list of configurations come up, type trackpoint into the filter area, you will see a ui.trackpoint_hack.enabled setting, change that from -1 to 1. Now you should be able to scroll using trackpoint and middle mouse button on the trackpad again.

This worked!

Thank you! Much! Works great!

You're welcome.

Please click the Helpful button next to the answer that solved your Firefox support issue, when you are logged in, so this thread gets marked as Solved to help other users who may have this same problem.

Actually. It worked for a while and now it stopped working!

I have gone back in and the value is still 1 instead of -1, but the wheel stopped working. I have restarted firefox and tried a few other refresh things but nothing. Will restart my computer and report back.

This didn't work for me. I am using a ThinkPad R61i. I have tried to see if there are any updates for drivers, and I have the latest. The scroll was working before upgrading to 4.0. Anything else that I can try?

After downloading and installing version 4, I have problems with my mouse scroll wheel. I also have problems getting to my bookmarks with ctrl b. When I type a ctrl b I get something called library and that does not contain all my bookmarks.This ( possibly others?) seems to last for several minutes. How long depends on whether I go ahead and scroll using the the scroll bar on the right side or not. If I do, it seems to clear up within 5-10 minutes and all works normally after that. This is EVERY time I load Firefox. I can get things working then exit FF and re-start it and am back to the same problem(s).

So far I have tried going into help and then selecting restart with addons disabled. and that didn't help. I have updated my mouse driver and that also has not helped. My next step is to go into view-toolbars, and deselect Google toolbar and see if that helps. I will report back on this ASAP.

My mouse is a Microsoft mouse 3000, and the driver is the latest according to the Microsoft page. Am hoping that I will have a dream tonight that will give me the answer, but hope that FF can do it even sooner. TIA.

I solved my problem(s) with FF version 4.0.1 this morning by uninstalling the version and re-installing version 3.6.17 immediately my problems went away. In my mind this proves the problem is in v4 and not on my machine.

If anyone is going to do what I did, I highly recommend that they download 3.6.1`7 before uninstalling v4, otherwise they might be reduced to using IE.

For me, this seems to be related to having PDFs open in the browser. If I go to the PDF and zoom in and out and close it, I can usually get it working again.

I use the middle button and trackpoint on my Thinkpad X200, tried the suggested fix, but no joy. Any other ideas? Is there a way to move back to the old version which retains all my bookmarks and links? Thanks

I tried the solution provided by the-edmeister and it seemed to help right away but now it's back to being squirrely. When I start up Firefox the scroll wheel does not work. If I click the scroll wheel button, then click it again, suddenly it will let me scroll, but only within that browser session. Once I close and then restart Firefox it doesn't let me scroll. Seriously annoying and making me consider reinstalling 3. PLEASE FIX!!!

Andy see my reply of a few days ago. The answer to your question is that you can go back to version 3.6.17. You will need to download the old version from http://firefox-3.en.softonic.com/ Save this old version (I saved to desktop) then go into Control Panel and delete version 4.0.1 After that you can run the file you saved and version 3.6.17 will be installed on your machine.

Hi there,

I have this problem now, too, with my mouse scroll wheel not working. I think it worked at first, when I installed the latest FF 4.0.1, but now it doesn't. It works in all other applications including IE. I don't know what happened, but I hope it's easy to fix, without having to re-install an older version of FF, or having to switch back to IE. Adjusting the the settings in about:config didn't do a thing, either.  :(

UPDATE: I found the problem. I had a site with a PDF file opened, and the tab for the site was "pinned" ( a new FF feature) As soon as I closed the PDF, my scroll wheel worked fine again.  :)

I notice a correlation between having pdf documents open and the scroll breaking. I think there is something to this.

Such a pain! If there's a pdf open, I can't scroll in other firefox tabs; close the pdf and scrolling works fine. Using a Dell Inspiron 1521. THANK YOU for figuring this out--I tried SO MANY solutions and wasted a bunch of time!

Bug has been marked as fixed, though it remains: https://bugzilla.mozilla.org/show_bug.cgi?id=594500

Bug says it was fixed in FF 9 so I upgraded to Firefox 9 beta and have not had the problem since

This seems to be a very common problem. My middle mouse button with laptop pointing stick does not scroll in Firefox. Does scroll fine in other Windows apps, Windows explorer, etc. I tried the beta and it did not help. I used Micrsoft's Spy++ to see what messages my system was sending. Interestingly, when I spy on FF, I see no wm_vscroll nor wm_hscroll messages (which I *do* see when scrolling in other apps) and only see lots of wm_nchittest messages.

Try installing WizMouse. It allowed me to overcome the mouse wheel problems that Mozilla either can't fix or doesn't choose to fix:

http://antibody-software.com/web/index.php?ref=wizmouse

I've had scroll wheel problems ever since Firefox 4, and each later release seemed to make things worse rather than better.

This is not solved. The issue still occurs in Firefox 8.0.1. As soon as a pdf is opened in a tab page, the scroll wheel stops working in OTHER tab pages. The above fix has no effect on any of the machines I tried it on: Win 7 & Win XP.

Actually this is a prety significant degradation in the user experience for those of us who are completely used to using the mouse wheel without even thinking about it. Going back to dragging scroll bars feels like wading through treacle.

I am surprised this bug has not had a higher priority. If there is a particularly thorny technical issue to overcome with it, then fine, just let us know, we will wait patiently, it's a free product after all, but it feels like this issue isn't deemed important enough to solve after 4 releases - I would argue strongly that it is.

Apart from this niggle, respect to all the developers and Mozilla crew - you are doing a superb and important job.