Antivirus personal error during the install of plug-ins

Hi there,
I have a problem with antivirus personal. Plug-in works just fine with Nu2Menu but with BS Explorer it gives an error. Exactly the same error when I choose what drive to scan with MacAfee scanner with GUI. Can anyone help me please to fix this problem ?
Thanks !

Antivir personalEdition Classic
B:Documents and SettingsDefault UserDesktop refers to a location that is unavailable. It could be on a hard drive on this computer, or on a network. Check to make sure that the disk is properly inserted, or that you are connection to the Internet or your network and then try again. If it still cannot be located, the information might have been moved to a different location.
