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Welcome to the forums, debbie.
The files listed below should be in a section of the Virus Chest titled "System Files." The avast program put them there as back up files just in case they are needed in the future. They are not infected.
kernel32.dll
winsock.dll
wsok32.dll
If you would like to test those files, you can right click each one and then click on scan. You can do this with any files in the Virus Chest. The only files that should concern you are the files listed in the section titled "Infected Files."
You can leave the infected files in the chest for as long as you like but we usually suggest leaving them there for at least 14 days just in case one or more are false positives. At the end of 14 days or more, you can check them again by using the right click method I mentioned above. At that time, you can delete them if you would like or you can just leave them in the chest.
I hope this helps you.
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