License won't activate
Check the key is correct, you're online for first activation, and the key isn't already bound to another PC. Try restarting the app.
Pro not unlocking after purchase
Sign out and sign back in. Paste the key in Settings → License. Check your email for the key.
Tweak didn't apply
Accept the UAC admin prompt. Some tweaks need administrator rights.
Game issues after tweaking
Revert gaming tweaks one by one — start with fullscreen optimizations off and MMCSS priority. Use Windows System Restore if needed.
License file location
%AppData%\IRIS Tweaks\license.json and applied.json