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What is 5d1c9gc7.default?

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Whenever I open firefox or go to a new webpage Avast spams me saying it detected a trojan. I opened up the virus vault and see that it blocked prefs.js, prefs-1.js, and elemhide-1.js and it all originated from 5d1c9gc7.default. elementhide-1.js was from 5d1c9gc7.default/adblockplus.

Whenever I open firefox or go to a new webpage Avast spams me saying it detected a trojan. I opened up the virus vault and see that it blocked prefs.js, prefs-1.js, and elemhide-1.js and it all originated from 5d1c9gc7.default. elementhide-1.js was from 5d1c9gc7.default/adblockplus.

Vahaolana nofidina

Sometimes a problem with Firefox may be a result of malware installed on your computer, that you may not be aware of.

You can try these free programs to scan for malware, which work with your existing antivirus software:

Microsoft Security Essentials is a good permanent antivirus for Windows 7/Vista/XP if you don't already have one.


Further information can be found in the Troubleshoot Firefox issues caused by malware article.

Did this fix your problems? Please report back to us!

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Vahaolana Nofidina

Sometimes a problem with Firefox may be a result of malware installed on your computer, that you may not be aware of.

You can try these free programs to scan for malware, which work with your existing antivirus software:

Microsoft Security Essentials is a good permanent antivirus for Windows 7/Vista/XP if you don't already have one.


Further information can be found in the Troubleshoot Firefox issues caused by malware article.

Did this fix your problems? Please report back to us!

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5d1c9gc7.default is your Firefox Profile folder, where your personal data and most add-ons are located.

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You can rename or delete the prefs.js file and possible numbered prefs-##.js files and a possible user.js file to reset all prefs to the default value.