I have deauthorized all but one device on iTunes. Yet, I still get the 'authorized 5 computers' warning. What. The. Heck.
Try "Deauthorizing All" then reauthorizing the one you still have as per the instructions: Deauthorize your computer using iTunes - Apple Support
Try "Deauthorizing All" then reauthorizing the one you still have as per the instructions: Deauthorize your computer using iTunes - Apple Support
I purchased a brand new MacBook Pro. Then, signed into my iTunes account. Then, deauthorized 4 older devices using the new MacBook Pro inside my iTunes account. I can’t imagine I then have to turn on EACH device separately and then deauthorize inside each separate device after logging into iTunes in EACH separate device. How would one do that on the device that burned in a fire? Impossible.
See Authorization vs. association - Apple Community. You cannot remotely deauthorize individual computers, but you can remove associations. I suspect that is what you've actually done so far.
tt2
Its unclear your meaning. You must de-authorize using iTunes on EACH device.
iTunes computer authorization issue
