Perhaps there is something wrong with your home page setting. To start Firefox up to a different page, try clicking a link in a document or email, or using a shortcut on your desktop. If you can get to a page, check whether your home page setting makes sense.

How to set the home page | How to | Firefox Help

If that doesn't work, try Firefox's Safe Mode. First, it's a good idea to make a backup of your Firefox profile folder that contains your bookmarks. For more information, see Backing up your information.

Next, try starting Firefox in Firefox Safe Mode. Be careful not to "reset" anything permanently if you didn't back up.

Does that fix it? If so, there may be a problem with an add-on or a "live bookmark" in your regular profile.

This issue can be caused by corrupted cookies.

Clear the cache and the cookies from sites that cause problems.

"Clear the Cache":

• Tools > Options > Advanced > Network > Offline Storage (Cache): "Clear Now"

"Remove the Cookies" from sites causing problems:

• Tools > Options > Privacy > Cookies: "Show Cookies"