Just noticed the following error message when trying to do an on demand scan started from the Icon in the task bar: Either there is no default mail client or the current mail client cannot fulfill the messaging request. Please run MS Outlook and set it as default mail client. I don't understand why I get this message. I don't use Outlook and my default mail handler is OE. In addition I have Opera set up for mail. Both seem to work fine. When I then try to run Nod32 via the control center I get the following error message : error occurred scanning MBR sector of 1. physical disk - error reading sector. When I run Nod32 from Safe Mode the error message is: error occurred while scanning operating memory. Operating memory cannnot be scanned ( an error occurred while loading nod32ml.vxd file or during communication with the testing service Any idea what all of that means, how it affects my "safety" and what I should do now?