Unknown user


Whenever I try to add some external users to a Teams team.  I'm seeing that their email address gets converted to Unknown User as soon as I select to add their email address.  Any ideas what is preventing me to add these users either via the web client or the Windows client?



13 Replies

Did you check Guest User setting configured on Azure AD?

@Zev Yanovich wrote:

Whenever I try to add some external users to a Teams team.  I'm seeing that their email address gets converted to Unknown User as soon as I select to add their email address.  Any ideas what is preventing me to add these users either via the web client or the Windows client?




Our Teams allows guests BUT 2 people I have tried adding change to Unknown User as soon as I add them.  If I go to Outlook to add them to the Office 365 group they show that they are added in with their correct names.  I also used the Teams & Skype admin center to check to on them but they are not listed there as users, neither is my gmail account which is functioning as a guest in Teams but my Hotmail account is listed there as a guest Teams user. The guest users are not able to access Teams.  I am trying to contact them to see if they have access to the other apps like SharePoint.  Does anyone know what I can do to fix this.


I added my personal gmail account to the Team just to make sure guests were getting in OK and I had no issues.  I also tested adding in a guest from another O365 tenant that did NOT have a Teams license and that worked PERFECT also.  I am not sure what else to do to troubleshoot this.  I will escalate to support soon but often times the amount of time spent on the phone with MS is beyond my tolerance in a day.  HELP

Have you ever found solution to a problem?
I have exactly the same issue. It's working fine for some external users, but some change to Unknown and i can't add them to another Teams. I get error: Unknown User
We ran into an issue. Please try again later.

Best regards
Best Response confirmed by ThereseSolimeno (Microsoft)


Our issue has been resolved however I am not positive what solved the issue.  I am an Office 365 Global Admin so I was able to go into AzureAD and check on the 2 unknow users.  One user it said had not accepted the invitation so I resent it from AzureAD and they go in.  The other user I noticed was a B2B connection.  I deleted them from AzureAD (they were a guest only) and then re-invited them into the Team.  In all honesty I was never sure if it was a temporary Microsoft glitch the 1.5 days of seeing unknown user or if my steps fixed the issue.  Sorry if this is not that helpful.

This did it for me. Deleting the external users from from Azure Users allowed me to readd them in Teams.

Worked for me too!

@Christine Stack @Zev Yanovich 

We also got the external guest error "we ran into an issue" when adding a person to Microsoft Teams.

We didn't have any luck with your solutions, but they gave us enough to find the following (which I hope helps others).


Situation : Had a project using a Microsoft Team, external consultants were added to the project using their email addresses e.g.

Some months later a new project was started with the same real people but the consulting company had been bought out so now Bob's email address became e.g.


Trying to add to the new project Teams site gave the "we ran into an issue" adding a guest error.


In Azure AD we searched for Bob McLastname and found


When we deleted from Azure AD we were then able to add him to the new project team without error using


Perhaps @Chris McNulty could bump this to the Teams Error message folks.

My use case would be : As a Microsoft Teams owner, I need to give my Tennant Admin a useful error message rather than "we ran into an issue" when trying to add a user via an email address which doesn't match an existing Azure AD guest user.

My guess is that both email addresses are associated with the same Microsoft Office 365 license thus causing a conflict, hence the error and why our fix worked.



What if you are not an Azure AD administrator?

@Christine Stack 

@Stephaniesmithif you are not an AzureAD admin I think you will need to ask your admin for assistance. 


I have heard that some people are just sending a file share to the guest (not an anyone link but a link that requires sign-in/sign up)  just so they get registered into AzureAd.  After they have successful access to a file share from OneDrive or SharePoint in your tenant THEN and maybe wait a few hours....then they are able to successful add them to a Team.


Give it a try and report back here.

@Zev Yanovich 

Just as an FYI.  Other than making sure the use is cleaned out of your AD or Azure AD.  I had to go to my Azure Admin portal and create a guest account for the external user.  Used that same account (I used a google account and used the same google email address to create a Microsoft account), This was done after I create the guest account in my Azure AD admin portal (Azure sent the invite to m google address)  After all this was done, I signed into my skype with my google address, looked for my Teams email address, and was able to go back and forth with no problem, but Microsoft seriously???! I have to go ALL THAT just to be able to talk to skype users?  That's just an insane amount of work when in the old days of Skype for business, you could EASILLY find an address and add with a click of a button.  That amount of work just to be able to talk to a skype for consumer user really?  Its just insane!

@Zev Yanovich 


We had the same issue, but this occurred after the domain was removed from our tenant and the other organisation set up their own tenant.


I tried, without success, to add this new external party to Teams, but received the same Unknown User error.


So went to Azure AD, created a guest user, went back into Teams and that seemed to fix the problem.


Just sharing in case this helps others.

@Christine Stack 

Deleting the user from AD solved the issue on our side as well. After that we were able to invite the guest user again in Teams.




It should be a HUGE AD/Teams/O365/??? issue. It seems that adding that guest user in Teams fails somewhere within several admin steps - but the teams doesn't rollback the complete transaction - the AD user remains active without Teams access. 


MS should fix this issue!!!


We tried to create a team of 50 guest - 10 of 50 failed and we had to delete the users manually on admin interface.... khm...




as a side note, did yo make sure the other Teams tenants had the switch on to allow all communications and collaborations with other Teams members.  If its not turned on the other members in other tenants wont be allowed to talk to yo no matter what you do.  That is of course up to the other Tenants admins for O365.  Also I assume you were trying to connect Teams users and not Skype for consumer users (You do that by adding the other users to your guest with the Azure AD admin webpage.) whihc by teh way is a bug (I called O365 team on a ticket about and it appears to be  a bug that has no resolution date to correct).