"You don't have permission to access..." errors are characteristic of a firewall that protects the server against misuse and this firewall thinks something is suspicious about the HTTP request. If you use a proxy or VPN then try to use a direct connection. Select "No Proxy" if "Use the system proxy settings" or one of the others do not work properly.

• Settings -> General -> Network -> Connection -> Settings

You can try to clear the Cache and remove the Cookies for websites that cause problems via the padlock button or via "3-bar" Firefox menu button (Settings) to see if that fixes it.

• https://support.mozilla.org/en-US/kb/firefox-cant-load-websites-other-browsers-can

I've seen cases where having enabled Resist Fingerprinting was causing this issue.

• https://support.mozilla.org/en-US/kb/firefox-protection-against-fingerprinting

Start Firefox in Troubleshoot Mode to check if an extension is causing the problem.

• https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode

If this all doesn't work then you can try "Forget About This Site" in the right-click context menu of an history item. Note that this removes saved passwords for this website as well.

• https://support.mozilla.org/en-US/kb/delete-browsing-search-download-history-firefox

I do not have a VPN but tried setting to "No Proxy" without success. It wasn't until I used troubleshoot mode that an extension was causing the problem. Thank you for your prompt response in correcting my issue. You are the best which is why I won't use any other browser!

Hello,

I am glad to hear that your problem has been resolved. If you haven't already, please select the answer that solves the problem. This will help other users with similar problems find the solution.

Thank you for contacting Mozilla Support.