Problem with two email accounts and contacts/calendars in Outlook

Copper Contributor

Hi, we need to have two email accounts set up in our Outlook (our own personal accounts). We then also have two calendars. These two accounts are located on separate tenants and each belong to separate "company".


We have several challenges with this:

  1. Sometimes we do not get new calendars added from the global adress list. They never appear in the list after pressing the OK button to add new contacts in calendar list/view.
  2. Sometimes we cant mark a colleague's calendar in the list and display it in Outlook. A restart of Outlook can (or not) fix it.
  3. You often look at calendars for colleagues if they are available and choose "new meeting with everyone" in Outlook. Then the message comes that "We will not be able to deliver this message to xxx xxx because the email address is no longer valid."
  4. We get error messages when we send out emails with the feedback of type: "The e-mail program uses outdated address information for IMCEAEX-_o=ExchangeLabs_ou=Exchange+20Administrative+20Group+20+2xxxxxxxxxxxx+29_cn=Recipients_cn=19xxxxxxxxxxxxxxxxxxxxXXxxXXxxX .COM. "

I suspect that all of these things have a connection and have spent several hours with Dr. Google to find a solution but can not see the pattern or what the problem really is other than that it has something to do with when one account will/tries to access/use the other account "contacts".


What I have tried is:

  • Remove all of the accounts and logins on the PC for account no. 2 and re-enter everything
  • Deleted the list for auto complete (locally in Outlook)
  • Removed cached Exchange mode
  • Deleted Outlook cache files locally on the profile
  • Updated Office (Outlook) software. (We uses Microsoft® Outlook® for Microsoft 365 MSO (16.0.14326.20706) 64-biters with Office 365 Exchange)
  • Turn off mail tips, turn off cached mode, start outlook a few times, turn on mail tips and cached mode again
  • Removed Offline address book and regenerated it.

None of this seems to work.


Really appreciate if anyone has an explanation for this or tips on what can be done to make this work. As it is now, Outlook appears to be "bingo" to use. Sometimes it works, other times not not ...

8 Replies


Edge confirms your account by default, so maybe adding a new profile to Edge would be helpful, but it's just guessing.

Yes, I have tried that too. There is a unlogical connection between accounts and services on the computer. The account can be logged on different places as Edge (profile), log in in Edge, Onedrive, account on computer, Outlook (email), Office account and Onenote. What login that connects and interact with another is not clear to me... But I have tried to log them all off and tried different ways on logging on again....


I would still check the defender firewall (add allowed application)
Of course, to Windows Add an account can also confirm this.


Yes, agree. When I do look at the settings Microsoft Office Outlook is marked on Privat (allowed) but not for public (not allowed). Should it be both?


So select both equally (you will check how it works) restart the computer.

Doesnt seem to do any difference. To me it looks like account 1 (from domain 1) does not see and does not have access to account 2 (from domain 2) and the other way so when we send mail or invite to meeting to the other domain we get the format "/o=ExchangeLabs/ou=Exchange Administrative Group (xxxxxxxxxxxxxxxx)/cn=Recipients/cn=xxxxxxxxxxxxxxxxxxxxxx-xxxxx" in the field for email adress.....


Yes and synchronization does not work for sure it is annoying

What if you added an alias to one of your accounts in Outlook?