Before the flash get's released. Here's how you flash a Buick using a Casper adaptor harness:
1) Do not try to open the flash update. Just save it somewhere on the laptop you use to tune your car.
2) Open up the XFI program. Plug the communication cable in. DO NOT ATTEMPT TO COMMUNICATE
3) With the ignition key turned OFF, go to the factory ALDL connector by the radio. Take a piece of wire (or a paperclip) and jumper the right two terminals in the top row of the connector.
4) Turn the ignition key "on". You should now see the "SES" light flashing rapidly and the "crank" light on the XFI box will be flashing.
5) Go to your laptop, DO NOT ATTEMPT TO COMMUNICATE. Click FILE, then FLASH XFI ECU. It will then prompt you for the location of the flash file you saved from this email. Select that file. Watch the screen very closely. It will show flash% and then it will verify. MAKE SURE IT VERIFIES
6) Once the above is complete, turn off the ignition and unhook the ALDL jumper wire.
That's it! If you have ANY questions or want me to walk you through this on the phone, just call