Hi, open 3-bar menu > Add-ons > Extensions, and remove (preferably) or disable Avast Online Security and Avast SafePrice, then restart Firefox. Either or both of those are prime suspects!

You could also look at Avast's settings, for anything else that might hook into browsers and turn it off.

If your question is resolved by this or another answer, please help other users by marking the best reply as Solved. Thank you!

When i try to attach a picture this is the response. I still need your help.

another pop up message

Did you try IE or Edge with OutLook? From my experience Outlook works better when using IE or Edge.

All of my email history is on this browser, if I change it maybe I will lose it. Furthermore this problem is recent. i have used Firefox for years with no problem. If you are replying on behalf of Firefox why are you suggesting i use another browser

You won't loose to just use IE to see what it does but if you don't try it then you will not find where the problem is coming from. Regardless of bookmark or not.

Hi again, open the 3-bar menu > Options > Privacy & Security, then under Content Blocking, remove all blocks; also under Permissions, deselect any block on Pop-up windows. Now reload the site. If that works, should you wish, you can make an exception for the site.

Also look in Avast and turn off HTTPS scanning to test if that's the cause https://support.avast.com/en-us/article/189/ Reload the page before trying again.

done as instructed but it made no difference.

Then you got problems you will have to take to a computer shop to diagnosis the cause of the problem.