Sometimes when I am working on my computer I get the following file appear on my desktop.

In the properties box is it listed as

Description '~' without inverted commas

Type of file: File

Size of file: 256 KB

Does anybody know where this file comes from and what it is, is it a virus, I run PC Cillin 2003 and the it is fully updated and scanned my computer and could not find any viruses.

Any help appreciated