What have you been doing on my machine ?
A few reg keys which you may find useful to find out what someone has been doing on your machine.
reg query HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\RunMR
reg query "hkcu\software\microsoft\internet explorer\typedurls"
reg query hkcu\software\realvnc\vncviewer4\mru
Get to this reg key via the regedit GUI (via run / regedit)