Recently my team and I developed some Mail Apps for Office and deployed them to an Office 365 tenancy. During the project we encountered a couple of important undocumented (well… at least I can’t find where it is documented) items with regard to the Mail App for Office deployment process. This short article describes these important tidbits of information and how they affect your Mail Apps for Office deployment process to an Office 365 tenancy. At the end of this article you’ll find links to the related Property Inspection Code Sample in the OfficeDev GitHub repository.
The first gotcha: no assigned Exchange license
First, the account you log in with must be a global administrator in order to access to Office 365 tenancy Exchange Admin center. This is pretty common knowledge and nothing new. The Exchange admin center looks like the screen below. In this scenario I am logged in with a global admin account that does not have an Exchange license assigned to it. Notice the list of Mail Apps is blank.
Here’s the first gotcha; although you can open the dialog to upload a Mail App for Office manifest when you are logged in with a global admin account, the upload process will fail when you attempt to upload the file. The error “The items you’re trying to open couldn’t be found” occurs (pictured below).
After you log in with a global admin account which does have an Exchange license assigned to it, things are different. First, now the list of Mail Apps for Office in the Exchange admin center displays all the Mail Apps for Office deployed to the tenancy (shown below). Second, you can now successfully upload Mail App for Office manifest files.
Next gotcha: User Default setting is disabled
The next gotcha is the User Default setting applied to a Mail App for Office after you upload a Mail App for Office manifest file. This setting now defaults to Disabled (shown below).
When the User Default setting is set to Disabled, a Mail App for Office will not activate when viewing an email that should trigger it to activate. In my example below, the Incident ID: <#> portion of the email should trigger the Property Details Mail App for Office to launch.
To change the User Default setting value, edit the Mail App for Office in the Exchange Admin center and select the Optional, enabled by default radio button (shown below) and then save the change.
You can see the User Default value is Enabled (shown below).
Now, when you return to Outlook Web Access and refresh the page the Mail App for Office appears. In the example below you can see the Property Details Mail App for Office is visible.
Property Inspection Code Sample GitHub resources
For more information about making Mail Apps for Office, see the Property Inspection Code Sample in the OfficeDev GitHub repository.
README: Describes what the Mail App for Office does in the Property Inspection Code Sample.
Mail App for Office Visual Studio Solution
Manifest: Shows how the Mail App for Office uses a regular expression to trigger launch.
My App – Mail App Controller: Used to retrieve information displayed in the Mail App for Office.
My App – Mail App View: The Views used to generate the user interface for the Mail App for Office. Notice there are two views. The Redir view inspects the email, parses the information, and redirects to the Index view where the Incident ID is used to load the data and bind it to the user interface. This is explained in more detail in the README file.