What is the exact error message?

Many site issues can be caused by corrupt cookies or cache.

• Clear the Cache and

• Remove Cookies

Warning ! ! This will log you out of sites you're logged in to. You may also lose any settings for that website.

Type about:preferences<enter> in the address bar.

• Cookies; Select Privacy. Under History, select

Firefox will Use Custom Settings. Press the button on the right side called Show Cookies. Use the search bar to look for the site. Note; There may be more than one entry. Remove All of them.

• Cache; Select Advanced > Network.

[v57+] Select Privacy. Across from Cached Web Content, Press Clear Now.

If there is still a problem, Start Firefox in Safe Mode https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode

A small dialog should appear. Click Start In Safe Mode (not Refresh). Did this help?

While you are in safe mode;

Try disabling graphics hardware acceleration in Firefox. Since this feature was added to Firefox it has gradually improved but there are still a few glitches.

How to disable Hardware Acceleration {web link}

FredMcD said

What is the exact error message? Many site issues can be caused by corrupt cookies or cache.

• Clear the Cache and

• Remove Cookies

Warning ! ! This will log you out of sites you're logged in to. You may also lose any settings for that website. Type about:preferences<enter> in the address bar.

• Cookies; Select Privacy. Under History, select

Firefox will Use Custom Settings. Press the button on the right side called Show Cookies. Use the search bar to look for the site. Note; There may be more than one entry. Remove All of them.

• Cache; Select Advanced > Network.

[v57+] Select Privacy. Across from Cached Web Content, Press Clear Now. I did the steps above, still same problem after restarting Firefox, but after restarting pc the problem was gone. Everyting running smooth now, thaks a lot FredMcD" :-)

Glad to help. Safe Surfing.