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All Firefox tabs say "123 | *computer name*"

  • 3 replies
  • 1 has this problem
  • 2 views
  • Last reply by FredMcD

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One of my company's employees called us because all of his Firefox tabs stopped showing the web site he was on and just shows "123 | *computer name*_*random string of characters*". His browser is also running slower. I looked for add-ons and recently installed programs and did not see anything suspicious. I Googled the random string of characters in the example I've uploaded and searched the registry. I found nothing. All of the forums I've found with "123" and "Firefox" were about viruses and had different symptoms than this. Firefox has been uninstalled and then reinstalled with our image and the problem persists. Any thoughts as to what could be causing this? Thank you for any help/information offered.

Dell Latitude E7250 Windows 7 Pro Windows Updates are current

One of my company's employees called us because all of his Firefox tabs stopped showing the web site he was on and just shows "123 | *computer name*_*random string of characters*". His browser is also running slower. I looked for add-ons and recently installed programs and did not see anything suspicious. I Googled the random string of characters in the example I've uploaded and searched the registry. I found nothing. All of the forums I've found with "123" and "Firefox" were about viruses and had different symptoms than this. Firefox has been uninstalled and then reinstalled with our image and the problem persists. Any thoughts as to what could be causing this? Thank you for any help/information offered. Dell Latitude E7250 Windows 7 Pro Windows Updates are current

All Replies (3)

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Did this employee do the usual troubleshooting steps?


Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration is causing the problem.

  • Switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Appearance
  • Do NOT click the "Refresh Firefox" button on the Safe Mode start window

Do a malware check with several malware scanning programs on the Windows computer.

Please scan with all programs because each program detects different malware. All these programs have free versions.

Make sure you update each program to get the latest version of their databases before doing a scan.

You can also do a check for a rootkit infection with TDSSKiller.

See also:

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I've run our main antivirus, but have not run malwarebytes (our backup) as of yet. Unfortunately those are the only two approved applications I can run. I will also run Firefox in safe mode when he comes back in tomorrow. He didn't have any extensions or themes installed, but it's always worth double checking. Worse comes to worst I'll just re-image the device, but I'd rather not do that.

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Anti-virus do their jobs very well (the good ones), but many of them can not detect Malware and some other stuff.