Compatibilitychecksvc.exe - by Ad Support.
What is compatibilitychecksvc.exe?
Compatibilitychecksvc.exe process belongs to AdSupport adware. This adware will display pop-up windows and in-text adverts on every web page you visit. I will redirect you to websites filled with ads as well. This adware comes bundled with other software, mostly potentially unwanted programs and freeware. It might be installed as a part of another adware. Usually, it's installed using silent installer in the background without your knowledge and permission. Once this adware is installed on your computer, you will notice that there are multiple processes (could be up to 20!) titled "compatibilitychecksvc.exe *32" and using 40% or more of your PC's resources. It does not have any version or vendor information. However, compatibilitychecksvc.exe is digitally signed even though its digital signature can't be verified at the moment. The biggest problem with this this is that you can't easily delete it because windows will tell you that these multiple instances of the file are being uses by another application. Once you end one of them using Task Manager another is quickly created. Compatibilitychecksvc.exe is not essential for Windows. What is more, it can crash your web browser and make your computer slower. I advise you to remove this adware and related malware from your computer. And don't forget to run a full system scan with recommended anti-malware software.
File name: Compatibilitychecksvc.exe
Publisher: Ad Support
File Location Windows XP: C:\Users\%USERNAME%\appdata\roaming\compatibility verifier\
File Location Windows 7: C:\Users\%USERNAME%\appdata\roaming\compatibility verifier\
Startup file: HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run → compatibilitychecksvc.exe