Looks like a few people are having login problems with Gmail Checker. Since this doesn't happen to me, it is particularly difficult to verify. It would be helpful if you could leave a comment if the extension works or doesn't work for you and your location, e.g. UK, US, etc.

For anyone having the problem, could you try version 1.3.1.1 which is just version 1.3.1 with maxVersion bumped to allow it to be installed on Firefox 3.5, and follow these debugging steps:

• Clear all of your cookies
• Log in (with the extension not the web form on gmail.com)
• If succeeds, please tell me the steps you've taken, e.g. 1-2-3 or 1-2-4-2-3, etc.
• If fails, go to http://www.gmail.com/, and then go back to step 2

Update: 18/9

I think I've found the cause. Please try this version, and report if it works.

Update: 21/9

Please try this version and report if it works (with the debug log).

Update: 22/9

Another version to test. If it doesn't work, please include the debug log in your report; otherwise, it won't be much help.

I've got a general idea about the problem but doing guess-debugging is no fun at all.