Having multiple applications that act as chat respective IM application but you want Microsoft TEAMS to be the default Instant Messenger application especially so Outlook e.g. shows the correct online/offline as well as free and busy status for employees and so they can start a conversation directly from there, you will need to make sure that Microsoft TEAMS is the default IM Provider.
This came up especially in combination with Cisco Jabber, that is often used as the software phone client for a Cisco phone system. This application might overrule the user settings and take presence especially in Microsoft Outlook. Cisco has an article about this here that talks about various registry keys. But this is actually not the direct solution for this issue.
In order to set TEAMS, if installed, the default application for your employees, it is easiest to engage Group Policies, GPOs, for this. Simply follow the below steps. Those settings will find out if Microsoft TEAMS is available and if so set it as default IM Provider. Close Microsoft Outlook and open it again and you will see the status icons and message box being associated with Microsoft TEAMS.
Of course, you could slightly adjust the suggested GPO settings and engage e.g. Cisco Jabber or any other IM provider available instead. Just have a look at the registry path HKEY_CURRENT_USER\Software\IM Providers and see what is available and set the GPO accordingly. All you need is the name of the sub key for the DefaultIMApp value.
Steps for the user GPO
- Create a new GPO (or chose an existing GPO)
- This will be a User Configuration
- Navigate to User Configuration\Preferences\Windows Settings\Registry
- Create a new Registry Item
- Settings on General tab
- Leave the Action settings to Update
- Hive: HKEY_CURRENT_USER
- Key Path: Software\IM Providers
- Value name: DefaultIMApp
- Value type: REG_SZ
- Value data: Teams
- Settings on Common tab
- Check Run in logged-on user’s security contact (user policy option)
- Check Item-level targeting
- Click on Targeting and apply the following settings
- The following steps make sure that this is only applied if Microsoft TEAMS is available as a IM provider
- Click on New Item and chose Registry Match
- Match type: Key exists
- Hive: HKEY_CURRENT_USER
- Key Path: Software\IM Providers\Teams
- It is good practice to provide a Description for this item – e.g.: This will set Microsoft TEAMS as default IM Provider for e.g. Outlook – if available as IM Provider.
Make sure the GPO applies to your users and you should be all set. This will make sure that even if a new application is installed and takes the IM Provider role over, that your clients will still fall back to Microsoft TEAMS. Of course, it will depend on when the GPO was reapplied and that the user actually closes and reopens Outlook.