Windows defender says I have virus, 3 other AV say I don't

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LonelyMan

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Jun 22, 2012
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Windows defender picks up Trojan:Win32/Dynamer!ac. When I click to clean, it fails after 2 hours.

I also used Malwarebytes, Emsisoft Emergency kit and Eset and none of them detect a thing.

So false positive or something more dark that only Windows defender picks up?

I am on Windows 8.1.
 

LonelyMan

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Jun 22, 2012
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I can't boot from the usb, I put the usb as 1 choice in boot order, before hard drive, and it says "failed to boot from device because device failed to authenticate". I am using an HP laptop.

Should I disable secure boot and enable legacy boot? I hope it won't wreck my pc if I do that.
 

Rogue Leader

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Yes in order for this to boot you will need to do that. When you reboot and its done, set the boot order back and turn back on secure.
 

LonelyMan

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Jun 22, 2012
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My laptop freezes. It boots from usb, says "windows is loading files" and freezes at the windows loading dash

Edit: Secure boot is disabled.
 

Rogue Leader

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Thats not good. I don't know why it would freeze like that,

This could be one of two things, either like SR-71 says its a false positive, or there is something else wrong because your virus scan shouldn't crash, and Defender offline should work fine.

At this point there is nothing you can do with it with this, maybe try the software SR-71 recommended.
 

Rogue Leader

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I would hope not, I didn't see anything about that virus attacking the BIOS so I doubt it. Try another bootable USB and see what happens.
 

LonelyMan

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Jun 22, 2012
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I will try Kaspersky Rescue Disk 10
 

LonelyMan

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Jun 22, 2012
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Kas[ersky did not work. Could you please give me some USB antiviruses or software that I can use to scan before Windows loads. Preferably one that can update or is up to date.
 

Rogue Leader

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WHat do you mean by did not work? Did it not detect the virus or it would not boot load?
 

LonelyMan

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Jun 22, 2012
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I don't think it was designed for USB key use. It did not even detect the key and booted straight into OS like normal.
 

LonelyMan

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Jun 22, 2012
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I only ran Windows defender in safe mode, and after detecting the same thing and clicking on "clean", it would hang for 1 hour, then give me error lol.

And no, I did not clear my old restore points.
 

Rogue Leader

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Possibly its held up in an old Restore point, like SR-71 suggested. With the av programs crashing on you I'm not sure what to do here.

www.bleepingcomputer.com has an excellent virus removal resource. You may want to try there.
 

LonelyMan

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Jun 22, 2012
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Are you talking about Sophos? I found a guide on their website how to use Sophos on USB and do the scan before Windows loads. I'll do that tomorrow though cause it's late and I'm tired. I'll keep you updated on the situation. I installed Reason Core Security and it found two dll, one high risk one medium......I feel like this laptop has been infested for the longest time, even with paid Emsisoft internet security, which is supposed to be the best....