Developer guide for using Group Policy Objects (GPO) (Windows)

They are used to pre-configure servers, autoUpdater and server management settings

You can read more about GPOs here

Copy the files from this directory (resources/windows/gpo) to C:\Windows\PolicyDefinitions - the file mattermost.admx should go in C:\Windows\PolicyDefinitions and the file mattermost.adml should go in C:\Windows\PolicyDefinitions/en-US.
Press Win + R to open the "Run" box
Type gpedit.msc to open the Group Policy Editor
Select "Administrative Templates" => "Mattermost" - either in "Computer Configuration" or "User Configuration" it shouldn't matter.
On the right side panel Select the Policy you want to update, eg, "DefaultServerList" then click the "Edit policy setting" hyperlink/button.
Select the "Enabled" radio checkbox and click the "Show" button under Options.
A new windows opens where you can add Multiple values for pre-configured servers, where value name is the Server Name and value is the Server URL. Example:

Value Name Value

Community https://community.mattermost.com
Now if you open your Mattermost desktop application you should be able to see the server in the server dropdown (team dropdown)