I just now tried it on my phone , version 148 and there virustotal site is working properly???

Also tried it in Browser DuckDuckGo and there the virustotal website works flawless.

seems to me a Firefox issue?

Link? What security software are you running besides MS Defender? Are you running pro version of Windows? If so, you should have Windows Sandbox enabled for testing. https://www.howtogeek.com/399290/how-to-use-windows-10s-new-sandbox-to-safely-test-apps/

Hi jonzn4SUSE thanks for the quick reaction. I do not use any other software than MS defender

It looks like FF149 has caused this problem. I do use some add-ons like Privacy Badger, Ghostly and uBlock Origin

maybe I try to stop these add-ons and try again

stopped Privacy Badger, Ghostly and uBlock Origin add-ons but that did not resolve my problem.

Hmmm.. I was able to go to https://www.virustotal.com/ just fine with Firefox 149.0 with uBO still active. It does redirect to https://www.virustotal.com/gui/home/upload .

Might try Firefox in Safe or Troubleshoot Mode ( Help -> Troubleshoot Mode ) to see if it works there.

thanks MarkRH , I tried it again and suddenly virustotal.com is working fine again.

must have been a temporary glitsch? anyway thanks for your help.

problem solved