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Each time I open FireFox AVG alerts that C:\Windows\SysWOW64\rundll32.exe is a threat that has been detected.

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My computer which runs Windows 7 has been very slow to start and open. When AVG antivirus runs its' regular scan it comes up clean but when I open Firefox I get the above message saying that a threat has been detected. I hit protect and sometimes I am prompted to restart to heal and sometimes I'm told that it is hidden and cannot be accessed. It does not happen when I open internet explorer. I use information clearing house as my home page and have not yet tried changing the home page. I've run Malwarebytes anti malware and it does not detect the virus.

My computer which runs Windows 7 has been very slow to start and open. When AVG antivirus runs its' regular scan it comes up clean but when I open Firefox I get the above message saying that a threat has been detected. I hit protect and sometimes I am prompted to restart to heal and sometimes I'm told that it is hidden and cannot be accessed. It does not happen when I open internet explorer. I use information clearing house as my home page and have not yet tried changing the home page. I've run Malwarebytes anti malware and it does not detect the virus.

All Replies (4)

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after deleting your user.js file it is good if you do a full scan with malwarebyte also

Modified by tadnyarahul

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dont forget to update malwarebyte to latest database before scan http://www.tadnya.net

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With the help of a friend I had tried that and Malwarebytes still did not detect the threat. At that point I bailed and got my computer wiped and all new software installed. I read a review on AVG antivirus that praised it for its' sensitivity but cautioned against "false positives" for that reason. I am beginning to wonder if it was not a false positive since it only came up when opening Firefox, but not in the full AVG scan.

   By the way I imported book marks from Firefox into Internet explorer which had never shown that warning and it began to show the warning on opening. It has me puzzled to say the least but thanks for your suggestions.