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Windows 7: dllhost.exe infected

02 Sep 2014   #1

Win 7 Home Pre 64 SP1
dllhost.exe infected

I have been working on this laptop for over a week with no solution even after searching the web for every possible solution.
Here is what I have seen so far. When opening task manager and looking at processes from all users I see
dllhost.exe*32 using upwards of 80-90% cpu utilization and an ever increasing size of the file to over 100 MB. Many sites say dllhost is a system file and needs to be kept. I have 4 other PC's and all have this file at 0% and about 2-3M in size.
I have removed the drive from the laptop and reformatted the C drive, re-installed the OS from a CD. After doing the first round of updates all seemed OK. After the next round of updates the dllhost file again started to climb. Below are the steps I have tried.
I have run Avast (full Scan), Malwarebytes ( Full Scan) Combo Fix with no solution. I have changed permissions on dllhost and replaced it with a known good file. I watched the size of the replaced file and it started at 750KB and after a minute it started it's increase and the CPU utilization also climbed.
MS support wants $ to "fix" it. Most of the web based "fixers" scan and find all kinds of errors but none list dllhost.exe so I am reluctant to spend money not knowing if indeed they will correct the problem. On top of this, this is not my PC and the owner has already purchased a new Win 8.1 machine. I guess I am just a geek that would like to find the solution.
Thanks for any help.

My System SpecsSystem Spec
02 Sep 2014   #2

Windows 10 Pro (x64)

You are looking in the wrong place, dllhost.exe is fine. What you need to look at is what dllhost.exe is running.

Use Process Explorer:
My System SpecsSystem Spec
02 Sep 2014   #3

Windows 7 Pro 32

Do you know it's caused by an infection or just guessing? Try scanning the file on it scans with 50+ different antivirus products.

Malwarebytes doesn't enable scanning for rootkits by default. You might try that as well.

There are a couple of suggestions here that are related to thumbnail cache problems:
Windows 7 dllhost.exe memory leak - Microsoft Community
My System SpecsSystem Spec

06 Sep 2014   #4

Windows 7

dllhost never shuts the f&&& off always wants to connect to the internet to spy
My System SpecsSystem Spec

 dllhost.exe infected

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