In case you want to change the Site Icon and replace it with your own companies logo, you can use a hidden site in the Collaboration Manger 365.

In order to get there, visit the CM 365 app. Move your cursor to the address bar and click between the top-level domain and the string query.

Now type 'SiteIcon/create' in the URL and press enter.

You now are on the hidden Collaboration Manager 365 site. Choose a file to set as Site Icon. Be careful to choose the right format (146 x 60p).

In order to reset your changes, click on 'Reset and save default Icon'.