In certain environments, installing the Teams app might not be possible, not even by the team owner.
There are two ways to enable the app anyway, though an approval of a Microsoft Teams administrator will be required.
Option 1: Allow team owners to install apps by themselves
This is the option Microsoft recommends. This option is active by default.
Sometimes, an administrator has disabled the option for the team owners to install apps by themselves.
This is how you turn it back on:
MICROSOFT 365 ADMIN
Open the link in Microsoft Azure:
https://portal.azure.com/#blade/Microsoft_AAD_IAM/ConsentPoliciesMenuBlade/UserSettings
Permit access:
Open link in Microsoft Teams admin center
https://admin.teams.microsoft.com/policies/app-permission
Choose the policy that is assigned to your Jira users in Teams (or if you just have the global one, choose this).
Make sure, that installing third party apps is allowed by the applicable app permission policy (or just allow the installation for our app “Smart Connect for Jira”).
Please note: It may take up to 24 hours for the app to be visible for users in Teams.
Option 2: Install the app for certain teams manually
MICROSOFT TEAMS ADMIN
If the above-mentioned options can’t be done, Microsoft Teams administrators can also add apps on an individual basis.
Open link in Microsoft Teams admin center
https://admin.teams.microsoft.com/policies/manage-apps
Search for the “Smart Connect for Jira” app → add it to the requested team using the “Add to team” button.
In case the app is not allowed by default, it might also be necessary to allow the app first (see above).
Heads up
In case you see this error below, it usually works and the app should be installed. There currently seems to be a bug on the Microsoft side regarding this.