To clear old Notifictions old try icons left in Notifictions
Remove the following key from your registry
Start - Run - Regedit
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\TrayNo
tify] "PastIconsStream"
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\TrayNo
tify] "IconStreams"
After which you have to kill the explorer process and restart it.
Take note that shutdown and restart won't do, u have to kill explorer.