"This computer is already associated with an Apple ID"
Purchased a movie from iTunes over Xmas to watch on my Mac, download didn't start and the above annoying message popped up. I have now spent hours trying every fix on the internet in order to watch the movie that I have paid for (I have also emailed support via iTunes help, no reply as yet....).
On my 2009 Mac I have 2 log-ins, one for my wife and one for me. We both have individual AppleIDs, neither of us use match or cloud services. Having read all of these forum pages I'm guessing the bug lies somewhere along the "associated devices" pathway (my wife's AppleID is associated with this Mac). Having now been made aware of this frustrating "90 rule" I can at least (finally) partly understand what is going on. However, unlike others on this forum I am not trying to re-download my purchased movie, but merely to download and watch it for the first time!!
Hopefully Apple support will come back with a resolution.
A couple of other related points:
Firstly, to those here who question why we may need to re-download our own material: movies take up a lot of HD space, so I delete them after watching, thinking I could easily re-download when needed (apparently not!). Note: this is not what I was trying to do when I encountered the bug, I'm merely explaining (to the doubters!) why the 90-day rule is frustrating.
Secondly, whilst trying to get Apple's support with this I had great difficulty with the "Report a Problem" screen in My Account (in iTunes). I'd click "Report a Problem", it would then say in small writing "Report a Problem" next to the problem item. I'd then click Done. No acknowledgement, etc. Go back and problem item wouldn't be highlighted..., rinse & repeat. Only through reading another forum did I discover that the little "Report a problem" writing that appears is actually a button to press!!!
BUT, after making the above discovery it gets worse! For the page that you go to says (to paraphrase) "there are no problem items to report". This was at the end of an evening where I didn't get to watch my movie, I wasn't impressed.
I eventually trawled through the iTunes "support" and have sent a description of my issue ("in <400 characters" !) via email. I'll update with Apples response when I get it....