Same problem. O365 environment. Any news/solutions?
Cannot install Outlook add-ins
We have started having an issue installing Outlook add-ins which were working last week.
We have an on-premise Exchange 2016 server but also have Azure AD with directory sync running.
The only change that I know of was that the Exchange server had some updates done at the weekend, dated 11/7
When we try to install add-ins via the Store link in Outlook 2016 it goes through to the install or get option and then fails with "Installation failed due to an unspecified error. Try again"
If you refresh the page we either get the same error or :
"Add-in failed to install
For this token profile, audience from inner token 'https://outlook.office365.com' should match audience of outer token 'https://outlook.office365.com/'"
I thought it might be users were logging in with a personal Microsoft account but Outlook uses their corporate account and there was a conflict.
But I've tried it on a laptop myself and ONLY logged on with the corporate account and still get the error.
This is now a major issue for us since a group of people need a specific add-in to help in their work so any suggestions very welcome.
I also found this error. I use only 1 account for logging in via both Web and Outlook program.
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The Exchange version wasn't updated. But some Windows updates were done at the weekend. There were actually more done last night as I was going to try rebooting the server to see if the problem would be resolved. But it is still the same.
The Exchange version is:
AdminDisplayVersion : Version 15.1 (Build 2242.4)
ExchangeVersion : 0.1 (8.0.535.0)
I don't know if the issue happened directly after the update at the weekend. I just know it was working early last week (Mon/Tues 5th/6th) and then someone reported the issue on Tuesday morning this week (13th).
Both updates updated the Malicious Software Removal Tool
The updates installed on the 11th were:
Cumulative update for Windows server 2016 (KB5004948)
Cumulative update for .NET 4.8 (KB5003542)
Updates installed last night (14th):
Cumulative update for .NET 4.8 (KB5004115)
Cumulative update for Windows server 2016 (KB5004238)
We had a problem with accessing the Store previously but I found the solution to this was adding the registry entries for TLS security. The new issue is not giving the same error messages.
My feeling is that it is some conflict between the Azure & internal A.D. accounts but I'm just guessing. I don't know if it would show up in any logs but I don't know where to look. There's nothing in the Exchange server main event logs.
Hi @JohnRInfoSystems ,
Welcome to Q&A!
According to your description, everything can work fine before you update your Exchange Server version. So, seems the recent update operation has been the most possible factor of your issue right now. In order to further research about your issue, would you mind checking which KB have you recently installed? You could also try running the command below in your EMS to to collect the AdminDisplayVersion number.
Any update, please feel free to post back.
Hi @Supsoontorn Jenchawalitmongkol ,
Do you mean that you do also have the same problem right after updating your Exchange server version? If yes, to further research about your issue, please help collect your AdminDisplayVersion number as well. If you have more detailed information, please feel free to let me know.