MS Teams - unable to search for a user externally

Copper Contributor


I'd like to ask if anyone knows how to fix an issue wherein a person cannot find another user externally in Teams however his colleagues in the same company can exchange messages to the same external user. Both the concerned user and the external user cannot find each other in Teams.

Thank you!

14 Replies

Hi @janefriolo ,


Is this when you are adding the external users email address to the big command bar at the top? Does it not come up with "Search for <email address>" externally? 



@Andrew Hodges It's the icon on the left side we clicked. The box with a pen. The user was getting "We can't set up the conversation  because your organizations are not set up to talk to each other." However his colleagues were able to message the external user. It seems to be an isolated issue.

Most likely one of your users is set to Teams only and the other one Islands. External chat will not activate unless your set to Teams only, otherwise that external chat happens in Skype for Business.

I would start there by seeing if users are set to different upgrade modes in the Teams Admin center.
Well islands sometimes will allow the chat but not always ;p. Anyway check the upgrade modes of each and let’s go from there.

@Chris Webb Does the whole org have to be teams only? or can a user be Teams Only and the Organization be Islands?


I am having an issue with ONE organization we can't seem to connect to. They are Islands, we are Islands, but I am Teams Only. 

You can be Teams Only, but the person you are trying to connect to needs to be Teams Only as well or logged into Skype for Business at the time. It also depends on if they have Skype for business On-prem and hybrid setup properly etc. as well. Lots of factors there, but to answer your question, Teams Only for a user should work properly.

@Chris Webb you are right about the factors. We have a company who is Islands, using o365 and they can communicate with other companies except us using Teams. We can communicate with other companies using Teams, except them. We both have tickets open and no one can tell us why this is a problem. 

DM me your account I can test yours. My guess you guys can initiate but people can’t initiate with you and since y’all probably configures the same can’t start with each other.

What is your upgrade mode?
Well we got mine working with you, so you know that's good to go. Best course is probably having people just stick to Skype Clients until they switch over to Teams Only for external chats. Anyway, keep us posted with your finding. Thanks!
Hi, I’m having trouble using my desktop teams.
I understand that I cannot use the family and friends option from my desktop, but when I built a business account on my desktop, no one can find me and I cannot reach no one.
How can I solve this?

@Danadkny Can you please share how did you create Business account? Is it in O365? If yes, is the domain published? What mode you are running in Teams?

im a bit mixed up..

i havent created a buisness, 

when you create/signin the Teams, it asks you for what purpose,

i wrote "the work" option , and apperantly since then only trouble,,,

the client on my PC doesnt let me add my "private/family" one.

both of them are under the same user mail that i used, the only differnce is that one i marked the work option and the second i market the family and friends option.


the resukt is that from my mobile- i see both accounts, and i'm exposable to my friends only from the "private family " one.

from my desktop - which i need to be able to be exposed, and perfrom calls, i see only the "work acount" and its not editable.


it sends me a message that its available only for mobile use?!

dont know what to do..

@Chris Webb 


We have Federated Trust setup with mutltiple domains and one of my executives can't search externally.  It was functioning and then stopped.  I've looked at his upgrade mode and he is on Teams only and still can't search for external users.  Because there are multiple companies with their own domains, communicating from company to company is considered external, until we get everyone on a common domain.   Would changing him to Islands create a huge problem?


For me, this was caused by Active Directory having "msRTCSIP-DeploymentLocator" set to "SRV:" for the user.
Clearing this attribute fixed it after it had synchronized to Microsoft 365.
Inspiration was from: