I installed Windows 7 (x64) using an install script that puts the user folders on a different drive (D: in this case).
All other programs except AVAST seem to be aware that the default "users" folder for this Widows installation is on the D drive.
AVAST instead, creates its own instance of the Users\Public\Desktop folder in the C directory and puts its desktop shortcut there. It seems it is not following the environment variable for the default directory.
In short, AVAST is putting its "avast! Antivirus" shortcut in c:\Users\Public\Desktop
and it should be in D:\Users\Public\Desktop (or whatever is set as the variable for the Users folder).
This is not a huge issue at all, I just thought you'd want to know. Very few home users install windows like this, but many big organizations do (so that the user data is separated from the OS).