When creating or editing a VMobile Object Configuration record, WinModern is not available among the picklist values for the Device. Only iPad and Tablet can be selected.
By default, the WinModern_vod picklist value is not among the Selected Values for the Device Record Type.
1. Go to Setup --> Create --> Objects --> VMobile Object Configuration.
2. Click on the TABLET Record Type.
3. Click on Edit next to the Device.
4. Add WinModern_vod to the Selected Values.
5. Clear Veeva Cache, now WinModern is available as a Device.
CRM documentation: Using VMobile Object Configurations