It sounds like you may be getting hit with fake virus detections screams, which are a forum of scam and malware.

I would run more scans with malwarebytes, and then follow up on the bleeping computer forum for more help

Also, install an adblocker in Firefox to help prevent this:

https://addons.mozilla.org/en-US/firefox/addon/ublock-origin/

Here is more detail on this scam: https://malwaretips.com/blogs/remove-windows-detected-zeus-virus-popups/

OK, after using the "How do I remove Zeus virus" procedure provide on <malwaretip.com> website including Malwarebytes on the order of 5-10 times since my original post, I am getting fed up! Situation can (appear to) be resolved from a few days to about a week and then repops unexpectedly... like today! I am using Firefox Quantum as my browser. I am NOT visiting questionable websites to best of my knowledge. Since I can use Internet Explorer to access the Malwaretip and other websites, it appears that Zeus is targeting Firefox. Need a permanent solution!

This is not a Firefox Issue. It is a User Issue.

Please use more than 1 scanner as each uses diff tech :

• https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-caused-malware

Save your Report and google each before deleting anything as do not want to delete something you need, If need help :

• https://forums.malwarebytes.com/topic/9573-im-infected-what-do-i-do-now/

Post in only 1 forum, then wait.

Go To The Forum and Get Help , Mozilla does not work on Malware ir Viruses it only provides the User with information. You have been Provided.

Please let us know if this solved your issue or if need further assistance.

If you see a message, can you post a screenshot? I bet you are running into a scam, https://malwaretips.com/blogs/remove-windows-detected-zeus-virus-popups/

I'd suggest running Malwarebytes regularly, running Windows Defender regularly, and keeping all software up to date. Also install ublock to block malicious ads, https://addons.mozilla.org/en-US/firefox/addon/ublock-origin/

Pkshadow said

This is not a Firefox Issue. It is a User Issue. Please use more than 1 scanner as each uses diff tech :

• https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-caused-malware

Save your Report and google each before deleting anything as do not want to delete something you need, If need help :

• https://forums.malwarebytes.com/topic/9573-im-infected-what-do-i-do-now/

Post in only 1 forum, then wait. Go To The Forum and Get Help , Mozilla does not work on Malware ir Viruses it only provides the User with information. You have been Provided. Please let us know if this solved your issue or if need further assistance.

Well, PARDON ME, Pkshadow for my honest follow-up inquiry! (1) I bow to your superior knowledge but this is NOT a case of PEBCAC!; (2) IF you read my last as well as my original post, you would have seen that I am using the procedures and apps provided in the Malwaretips how-to including ADWCleaner, Malwarebytes, HitManPro and even Norton Power Eraser. Typically these apps are not finding any threats; (3) I understand that Mozilla/Firefox does not work on malware BUT it would not be the first app to be vulnerable to crapware; (4) To Tyler's point, the issue is the Zeus "creapware" which locks up the Firefox app and warns to not shut system down and to call 1-800-scr-ewme; (5) I DO run Malwarebytes regularly; (6) I have installed uBlock as well as PopUpBlocker Ultimate and these have not prevented recurrence;

Not sure what else I can do that is either preventive or corrective!

If you are seeing a message telling you that you have the zeus virus and to call a number to remove it, then it is a scammer trying to get your information. DO NOT CALL THAT NUMBER. You do not have a virus, this is nothing more than a scam ad. Ignore it, close the tab, and continue on your way

Tyler Downer said

If you are seeing a message telling you that you have the zeus virus and to call a number to remove it, then it is a scammer trying to get your information. DO NOT CALL THAT NUMBER. You do not have a virus, this is nothing more than a scam ad. Ignore it, close the tab, and continue on your way

Typically the whole screen is red, tho' in one case blue, with the message to call. I have not and will not call any of the numbers. As indicated when this screen appears, Firefox locks up...tabs cannot be closed, etc. When this happens I get onto Explore which operates fine and open the Malwaretips link to removing whatever the infectioni is. Should I just open Task Manager and shut down Firefox and then reopen but not Restore Open Tabs from previous session?

Did you also search online on how to remove and clear out the Zeus virus? That should be where you should also look.

Yes, I have searched the removal but this has not prevented recurrence.

I see you are ignoring the most important part of my answer to you. If need help : https://forums.malwarebytes.com/topic/9573-im-infected-what-do-i-do-now/ Post and wait.

This is not a Virus Removal Forum, let the people that do that help you.