The characteristics of files that should be exposed to be suspicious of virus are as follows:
1. Has folder icon but has extension such as '*. exe' or '*. scr' and has a size when viewed with the display Details. To view details on the Explorer go to "View" > "Details".
2. Has a name which similar to a file or folder.
3. Has not more than 1 Mb or less than 1oo Kb.
4. Has weird icon and not according to the extension, such as Adobe Reader Document, Microsoft Office Ducument (doc), or image files such as compressed 'zip'/'rar' but has 'exe' extension.
5. It comes back again after it has deleted.
