Granite Apple wrote:
One other observation: while chatting with someone at the Genius Bar regarding this problem, he mentioned that he wasn't able to check my AppleID's for alternate email addresses overlapping with my active email because the iTunes support team is a separate group (when I asked if AppleID's were handled by that team, he said they were).
Coincidentally while I was waiting for him to check some things, I noticed that my wife's iPhone was prompting me for my own AppleID password (not her password) to update an app.
At some point I apparently installed several apps onto her iPhone using my AppleID instead of hers. Not sure if this has anything to do with this issue, but I'm going through the process of checking every one of her apps in iTunes (by doing a get info on each of them) and deleting any apps from both iTunes and her iPhone that were downloaded with my AppleID.
I should read this thread more often - I forgot all about noticing this until restoring my iCloud account to my new iPhone after doing a backup on my old iPhone.
Before I finished restoring the apps, invites worked fine. They continued working fine while my phone was stuck in "restoring from backup mode" and kept prompting me for my wife's AppleID. As long as I didn't enter it, invites continued to work.
Once I entered her AppleID, invites stopped working - apparently at that point my iPhone installed one or more apps associated with my wife's AppleID.
Once I realized this, I tried de-authorizing my wife's AppleID from iTunes on my Mac (I previously hadn't realized i had ever authorized it), and then snynced my iPhone again. (I believe that the reason I had my wife's apps on my iPhone is because i plugged her phone into my Mac to charge it once, which triggered iTunes to start syncing - although not totally clear on how iTunes merges or not apps when you sync with multiple devices).
Invitations are now working again.