Mike_two:
I've learned a little more about this. In my case, I issued CCT seats to several endusers in one "session". All invites were caught by our spam filters, except for a new hire. There was nothing there for him, even after two follow-up attempts of removing and re-issuing his seat.
In our email system logs, we found where all invites had “knocked on our door”, including the “missing” invite for the new hire. The subject was the same for all, except the new hire - it was blank. Digging further, we found that it been rejected/bounced because our email system had not yet synced with AD, so it didn't recognize the new user account.
After a less than productive chat session w/Adobe Support, I called them, explained the situation, etc. The Support Rep I spoke with put me on hold to investigate on their end. Upon returning, informed me that the enduser's email address had been added to Adobe's email suppression list - the invite never left Adobe. I presume this because the first email from them had gotten bounced.
Long story short, the Support Rep has put in a request to have the affected user’s email address taken off of Adobe’s suppression list. He said it’ll take 24 hours for this to be done. It remains to be seen whether or not this will resolve the issue, but I'm hopeful/confident the CCT invite email it should at least “make it to our door”, this time.
I don’t know if this will help (hope so), but I thought it worth mentioning.
Don