NIS 2010 and pen drive

I am using NIS 2010 5-user pack on WinXP SP3.

Motherboard Gigabyte MA78GM-US2H.  Processor: AMD Athalon X2 550 2 GB RAM

 

Whenever I insert a pen drive (i have tried 3 different ones) into the PC the pen drive light starts blinking fast.  The pendrive is not displayed in Explorer.  It does get detected becuase the icon for removing the drive shows up in the task bar notification area.  The CPU usage goes to 100%.  I am unable to enter the Dismanagement area.  If I try to Stop the removable storage service in Services it says Stopping... and hangs from  that point onwards.  I even reformatted the pendrive.  My NIS is updated with the latest updates as of today.  Same with Win XP Pro.

 

If I disable antivirus auto-protect the blinking lite on the pen drive goes solid.  However I still cannot access the drive or do much as the cup is at 100%.  I am unable to end any of the associated processes.

 

If I disable auto protect and restart the PC I am able to access and use the pen drives without any problems.  A month ago I was using NIS 2009 and everything worked fine.  I had tried a trial version of NIS 2010 before formating my PC and had the same problem with the pen drives.

 

I have NIS 2010 on a Win 7 machine and do not pace any problems there.

 

Any idea on what I can do....  Thanks