Does your target have any connection to earth ground? In other words, is it possible that you have a ground loop between the PC's USB connection and that other ground? Grounded power supply? I have run into a similar problem - not sure if the error message was similar (too long ago) and I think I even toasted an ICD2 about that same time. Removed the ground connection from the PC (ran my laptop on battery with the AC adapter completely disconnected) eliminated that problem. Even connecting the ground lead of a scope probe (also connected to earth ground via the scope's AC power cord) can mess up an ICD2 project. I haven't yet invested in a USB isolator (BB Electronics) but plan to do so at the first hint of a similar project (one that requires a hard connection to AC protective ground). dwayne At 03:46 PM 11/27/2007, Bob Axtell wrote: >At my client office, with MPLAB7.4, it worked some but was very >cranky on my office Dell Dimension 2400. Lately, it has stopped >working entirely. But I can take the proto home, attach one of my 4 >ICD2's and they all 4 work perfectly. Yet at the office, not a >single DELL will run the ICD2, and we have 12 of them! -- Dwayne Reid Trinity Electronics Systems Ltd Edmonton, AB, CANADA (780) 489-3199 voice (780) 487-6397 fax www.trinity-electronics.com Custom Electronics Design and Manufacturing -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist