And if that's the case, please click on the link below and follow all of the steps in the order they're given, to the letter. The scans provided should remove any malware found. Since it's possible you can't download the files mentioned on your "problem" computer, use a second 'clean' computer to download the files, then copy them to a CD or flash drive. Transfer the files to the problem computer and run them in the order mentioned.
“Expand” the post titled: "Please try this" at the link below:
http://www.cnet.com/forums/post/f742c795-5881-433b-a29b-6d758efe5cd3/
On the other hand, if you're unable to login to normal Windows, then use a separate "clean" computer to visit the Windows Media Creation Tool for your operating system, then create a Windows installation disk for reinstall or run a repair install of the computer. (See the link below.) Of course, if you have a brand name computer, you should be able to visit the computer manufacturer's site and obtain a recovery disk cheaply.
https://support.microsoft.com/en-us/help/15088/windows-create-installation-media
Unfortunately, you've not given us any information about your computer such as make and model, operating system installed, what you "downloaded but you shouldn't have" or anything else. That information would sure help us to provide more complete answers.
Hope this helps.
Grif
So I downloaded something I shouldn't have, now I have things called Blunt.exe running at all times, i've tried getting rid of them but no dice, and they're causing annoying audio adds to play from an invisible area of my computer, I've tried to do a reset, even factory reset of my computer but I cant access it. I cant even boot up my computer in safe mode or activate a reset via command prompt. so is my computer just screwed? and is my only option to take it to some guy who'll have me pay an arm and a leg to fix it? I want direct answers so if anyone sees this, e-mail me at: email address removed by moderator because it's unsafe and all responses will be in this thread so all can see.

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