They were the first ones I tried removing, hmmm, I'll have a fiddle about. Thank you for the reply you've saved me a lot of time :smile: Edit: In case anyone else finds this thread, it was the Rebuilt Kingsport Lighthouse. It must install the clean windows without asking; whereas the others in the Rebuilt series seem to all have the option not to install the windows. Deleting the 9 window texture files it adds under Architecture fixed it.