Hi Gang, I just went into a lab and fooled around with the two PCs we have hooked up to PICStart Plusses. In doing this, I found a couple of things that may cause problems: 1. Check the version of the PICStart plus software that you are using. If you don't delete 1.01 before loading 3.10, 3.10 will pick up 1.01 and use it (before and even if you load in 1.20 afterwards, which is the correct version). From what Ray said happened, this seems to be what happened on one PC when I tried reloaded 3.10 with PSP 1.01 still loaded. 2. In your Windows Directory, there is a file MPLAB.INI. This should also be deleted (and was in the "Terminate with Extreme Prejudice" comment earlier) because 3.10 seems to pick it up and it doesn't work correctly. When I was going through the two PCs, I also found .DAT files in the MPLAB directories, I don't know if deleting helps anything, but I did and didn't have any problems. One of the PC's is running Windows for Workgroups while the other is running 3.10. Both are running MPLAB 3.10.03 with PSP 1.20 without any problems. Good Luck! Myke Do you ever feel like an XT Clone caught in the Pentium Pro Zone?