Teams chat - adding external users..works for most, but not a few

Question

I'm not new to Teams; working with it over 1.5yrs. But I don't classify myself an expert...however...

problem: my company allows external users and guests to be added to chats and teams channels (part of our business need). Hundreds of users, but found at least 3 who can not 'add external user' in their chat within Teams...

I'll explain: user.one@domain1.com, user.two@domain1.com, user.three@domain1.com, external.user@externaldomain.com

our users are "domain1"..."user.one", a co-worker (different department but has the same policies as someone from his department) is "user.two" and another coworker is "user.three".

if "user.one" and "user.three" search in teams app for "external.user@externaldomain.com" -- we can add/chat, etc with external.user@externaldomain.com. (this is also proven that we have the settings right / I've confirmed them many times for the policies for everything).

however, "user.two" - searches for the same external user "external.user@externaldomain.com" (which was found by 2 others no problem)--they are not able to even click "search externally" as it doesn't show.

I've reinstalled the app on the PC, verified the same policies in place as the other 2 test users; even tried it on another PC and "user.two" can not search externally (must be a profile issue).

I'm stumped...anyone have ideas what could be causing this problem? I've gone through all the settings, even checked again in powerShell. I'm a few hours from opening a ticket with Microsoft on this one...so far, only a few users have this problem and it appears to be a profile issue/setting...I'm just not seeing it. We did have Skype for Business but we have long since shut down and converted everyone to Teams.

thanks!

Answer 1

@JimmyYang-MSFT When you say disable this user, where exactly, ie. Teams admin center, AD, AAD? What is the intended goal of disabling them? If you disable them, and then recreated them, you'd have two profiles essentially. My issue is that internal user Marcy can't get a status of one user at external domain but others in the company who teams chat with those same external clients aren't having the same issue. The external user in question also doesn't see the status of internal user Marcy. Both indicate offline when user is clearly not offline.

Answer 2

Hello!

Well, after working with a Microsoft Engineer for a few weeks, we finally figured out what the problem was and how to fix it.
As we came from a Skype for Business deployment and moved to Teams, there was a setting in Active Directory (on prem) which didn't get changed.
The user profile account in AD - Attributes tab, the property of "msRTCsip-UserEnabled" was set to "false". Change the Attribute to "True" and wait 24hrs for everything to Synch.
We had 3 users affected with this problem and once that attribute was changed in AD & 24hrs passed, they were able to find all external users. This was our resolution in my case. Have a look to see if any of those "msRTCsip" settings are different from the failing user to another user; you may find the problem.