Well color us completely confused. I just tried to log in from an IE7 computer with a different FB test account. No errors. Then I logged in with the account I had registered with earlier. Again, no problems. Other than the same IP, these are completely different computers.
Can you tell me if you were already logged into Facebook when you were trying to log in through your site? Obviously, this shouldn't be a problem, but really trying to wrap my head around it.
A few things to try. First, after looking at your Facebook Application page on Facebook.com, I noticed that your Site URL is actually the semi-secret URL you sent to me. Can you please update this to just your main site's URL:
domain.com/ (no sub-directory). This shouldn't be the cause of the problem, but is a/the proper way to setup your site URL.
Additionally, if you're comfortable making a small code change, can you try the following? This will bypass the 2nd set of permission requests, as I mentioned above. It also may fix the issue since it's where the 'next' URL is specified, which is causing the error.
In the /components/com_jfbconnect/libraries/facebook.php file, at ~ line 108, there's the following code:
if (FB.getSession())
{
self.location = "{$optionPermsUrl}";
}Can you change the variable inside the {} to $loginLink, so it looks like:
self.location = "{$loginLink}";
Please, report your findings, cause I'm very curious to hear how this goes. I actually think the first change (changing your site URL) is the most likely culprit as it's possible IE is encoding something strangely. Then, when Facebook checks
blah.com/123 to the encoded version (http%24%35%35blah%20123), it balks thinking they're different. However, I think both options have a chance at fixing the problem.
As you can probably tell though, you're in a pretty unique situation and we're drawing at straws.
Thanks!