The error occurs when trying to get to the login page, or after entering your login information and submitting it?

Some general suggestions:

When you have a problem with one particular site, a good "first thing to try" is clearing your Firefox cache and deleting your saved cookies for the site.

(1) Bypass Firefox's Cache

Use Command+Shift+r to reload the page fresh from the server.

Alternately, you also can clear Firefox's cache completely using:

"3-bar" menu button (or Firefox menu) > Preferences > Advanced

On the Network mini-tab > Cached Web Content : "Clear Now"

If you have a large hard drive, this might take a few minutes.

(2) Remove the site's cookies (save any pending work first). While viewing a page on the site, try either:

• right-click and choose View Page Info > Security > "View Cookies"
• Tools menu > Page Info > Security > "View Cookies"

In the dialog that opens, you can remove the site's cookies individually.

Then try reloading the page and logging in again. Does that help?

In case one of your extensions is involved, could you test the page in Firefox's Safe Mode? That's a standard diagnostic tool to deactivate extensions and some advanced features of Firefox. More info: Diagnose Firefox issues using Troubleshoot Mode.

You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" button > Restart with Add-ons Disabled
• Help menu > Restart with Add-ons Disabled

Not all add-ons are disabled: Flash and other plugins still run

After Firefox shuts down, a small dialog should appear. Click "Start in Safe Mode" (not Reset).

Any difference?

1 - error occurs on login page of bronxnet.org

2 - clearing cache has no effect

3 - clearing all cookies has no effect

4 - entering safe mode lets me in w/o error. So this means one of the add-ons is the cause. How do I re-enable them one at a time to find the culprit?

Thanks for the quick reply!

You didn't include a list of your extensions, but as a matter of general principle, the ones most likely to cause this kind of issue would be blocking something, such as cookies, information about the referring page, or information about your browser.

You can review and selectively disable extensions on the Add-ons page. Many extensions also have an Options button, so it might be possible to make a site-specific exception to the blocking. You can start here:

• Command+Shift+a
• "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Extensions.

Note that once an extension is disabled, when you return to this tab, it will be grayed out and appear at the bottom of the list.

Can you track it down?

Umm, forgot to mention that in Safe Mode, you can't re-enable them. You'll have to experiment in Firefox's normal browsing mode. (Exit Firefox and start it again normally.)