Thumbs.db file is generated by virus in most of my folders of the computer. How to clean the virus. Please help me in this regard. I have cleaned my computer with Mcafee anti virus but this has not helped. Please advice.

Thumbs.db is not a virus, it is a system generated file in folders that have images in them.

Here is some info with some options
Get rid of Thumbs.db (http://www.ofzenandcomputing.com/zanswers/98)