I've been using my ICD2 for a while now and haven't had any trouble with it. Yesterday, I decided to get a second development system up and running, so I installed Mplab and Hitech on the second system. Everything seemed fine, there were no errors when I built the software and no problems connecting to the ICD2 in debug mode, even program and verify was successful. However, after program and verify I keep getting an "Unable to enter debug mode" error. I included the log below. After the error, I can do all the normal debug actions (run, halt, step) and the code is executing as expected. Both systems are using Mplab v8.63 and Hitech PIC18 v9.63PL3 and the same source code. The only difference is that the newly configured system is WinXP and the old system is Win7 64. Any ideas how to get rid of the error? I remember when switching computers a while back, the ICD2 automatically download new firmware. Does the ICD2 need different firmware depending on if it's operating from Windows XP or Win7 64? If so, how do I force that download? Thanks, David ++++ MPLAB ICD 2 ready for next operation Programming Target... ....Validating configuration fields ....Erasing Part ....Programming Program Memory (0x0 - 0xBF) ....Loading DebugExecutive ....Programming DebugExecutive ....Programming Debug Vector ....Programming RSBUG Verifying... ....Program Memory ....Debug Executive ....Debug Vector ....Verify Succeeded Programming Configuration Bits ... Config Memory Verifying configuration memory... ....Verify Succeeded Connecting to debug executive ICD0083: Debug: Unable to enter debug mode. Please double click this message for more information. MPLAB ICD 2 ready for next operation --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .