Your screenshot shows xDecoder reporting that the license file is missing or corrupt. The HWID 9091F23B3ACC7F80 is visible in the dialog.
Import the .reg license file you received and restart xDecoder. If you don't have the license file yet or it was lost, post the full HWID so it can be issued:
HWID: 9091F23B3ACC7F80
Once you have the .reg file, double-click it to merge it into the registry, then launch xDecoder again.