Its possible if you have already run a virus scan and tried to block ads. However, some websites can detect that you have an ad blocker and not all ads can be blocked. How do I turn on the Do Not Track feature?

Your System Details shows;

Installed Plug-ins

Shockwave Flash 15.0 d0 Shockwave Flash 11.7 r700

Adobe Shockwave for Director Netscape plug-in, version 12.1.1.151 Adobe Shockwave for Director Netscape plug-in, version 12.0.4.144

Having more than one version of a program may cause issues.

Flash is notorious for not cleaning out the older version as part of an update. Grab the uninstaller from here: Uninstall Flash Player | Windows Uninstall Flash Player | Mac Then reinstall the latest version.

Shockwave Flash v15.0.0.152 http://get.adobe.com/shockwave/

Click the icon for AdBlock and make sure it is enebled.

Adblock Plus Homepage {web link}

Thanks FredMcD, but this isn't the case. I usually visit the same website, rarely do I visit other sites, and this is happening on sites I've always visited and had no problems. I've reset Firefox and it helped some but it's still not working properly. It's crashing, slow, and unresponsive. Tried IE and not crashing, slow or unresponsive. So has to be Firefox. Pity, I've been using this browser since the mid or late 90's. It was my favorite because if I ever had issues all I had to do was search online for the fix, but I no luck fixing whatever this is and will probably look around for a new browser if I can't repair this. Any suggestions for a good new browser?

Already uninstalled flash player and reinstalled it. Did not help. Do I need the shockwave player? I uninstalled that one too, but reinstalled it also.

Adblock is enabled. First thing I checked. Also I've uninstalled and reinstalled several times. Was running Ghostery with it and uninstalled Ghostery in case of conflict. Still didn't really help.

Did you use the link I gave you for the Adblock home page? You can get better add-on help from the writers of that program.

One thought is to save everything, remove Firefox, do a fresh install, then check for problems.

Uninstall Firefox from your computer {web link}

Download Firefox Full Installer For All languages And Systems {web link}

These add-ons can be a great help by backing up and restoring Firefox

FEBE (Firefox Environment Backup Extension) {web link} FEBE allows you to quickly and easily backup your Firefox extensions, history, passwords, and more. In fact, it goes beyond just backing up -- It will actually rebuild your saved files individually into installable .xpi files. It will also make backup of files that you choose.

OPIE {web link} Import/Export extension preferences

Reset Firefox {web link} is a LAST RESORT ! !

Reset Firefox -- easily fix most problems

If you're having problems with Firefox, resetting it can help. The reset feature fixes many issues by restoring Firefox to its factory default state while saving your essential information like bookmarks and open tabs.

Thanks Fred, I uninstalled Firefox and Nightly and only re-installed Nightly. Left off most of the other add-ons and it's working much better. It's still slightly sluggish but it's not hanging up and dragging like it was. Ad Block is working again also and doing its job of blocking ads. Thank you again.