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Hi Community!
I'm having problems with my custom add-in for outlook. I usually install it from url manifest in the M365 admin center without any issues.
However I need to install the add-in on an OnPrem Exchange Server using Outlook 2016. I tried through the 365 admin center. The add-in is installed but don't show up in outlook.
I ended up installing it through Exchange Admin Center -> organisation -> add-in -> add from url. I got this error: "Value can not be null. Parameter name: constraintProvider"
I ended up downloading the mainfest og added the add-in from file. The add-in showed as it should in the toolbar and I thought we had solved the problem. However when we tried using the add-in, the task-pane/sidebar was completely blank. Nothing to show.
Can anyone help?
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Hi @Runebk
What's the result if you download the add-in on your outlook O365 use the method "downloading the mainfest og added the add-in from file"? Do all the users or clients have this issue using this download method?
The client doesn't have acces to web-based outlook unfortunately.
This is the first time I try to install it at a client that doesn't use M365 (users are not connected to M365) or at least the first time I couldn't go through the M365 admin center.
Hi,
Can this be related to the requirement of this add-in? For example, it needs M365 account license or permission?
Or check if it's related to the install method, try using the same method install this add-in for users connected to M365, check if it can work properly.
Hi,
Is there any progress about this question so far?