I don't have that issue that your referring to. IE11, Edge, Chrome has no issue getting to gmail. Did you try other Browsers to know if it was a site or Browser problem as well?

Its not working only in mozilla...i tried to open it on chrome and there wasnt any problem, so i really dont know what is not working here..

See: https://support.mozilla.org/en-US/kb/websites-dont-load-troubleshoot-and-fix-errors#w_the-problem-only-happens-in-firefox

Hi, hold down Shift when you start Firefox to start in Safe Mode. More - Diagnose Firefox issues using Troubleshoot Mode. If it works in Safe Mode, disable any theme or add-ons you have - Add-ons Manager (Ctrl+Shift+A) > Themes/Extensions, then if it's OK, re-enable them one at a time until you find the culprit. You may need to restart Firefox after enabling some add-ons.

if Safe Mode doesn't help, try deleting ALL references to Gmail. To do that, open the 3-bar menu > Library > History, then click the Show All History link at the bottom of the list to open the History-library window. Search for Gmail in the Search History field in the top-right corner, then press Enter. Now in the search results, right-click on Gmail, and select Forget About This Site. (Browsing and download history, cookies, cache, active logins, passwords, saved form data, exceptions for cookies, images and pop-ups for that site will be removed). Give it a minute to complete the deletion, then try the site (not from an old bookmark) again. More - Delete browsing, search and download history on Firefox

If your question is resolved by this or another answer, please take a minute to let us know. Thank you!

I didnt manage to solve the problem, but i figured that when i try to conect to my mail i got this error message..Scribe your 2nd solution helped me to at least type my gmail into sing in but when i connect it and allow via my phone i just got this error message..i Tried to reinstall mozilla but i didnt solve the problem..

Are we talking about android FF here or Windows related FF? The last response I read is confusing.

heh, we are talking about windows, my mail is working on my phone, but not on my mozilla firefox... I managed to reach the steep where you write your adrese, then gmail is offering to customer conecting via your mobile by accepting message you get on your phone so you dont need to type password of your mail, that conects automaticly, but again i didnt manage to open my gmail, instead of gmail page i got error page. I hope you understand it. :)

I am sorryI do not associate my problem with any of these - I might be looking at this from the wrong angle BUT - once - quite a while ago I was able to read Gmail on Thunderbird - now I am unable - to do sob I have myt Thunderbird open and it has all from the 25th of this month BACK - but Gmail keeps refusing to civvy up any others - I want my Thunderbird back Incredimail can go and - err - y'know