Starting October 16, 2017, users running Windows 7 will no longer receive updates to Proclaim.
If you like Windows 7, you can still use it for now, but you'll need to update to at least Windows 7 SP 1.
For the best experience going forward, we highly recommend upgrading to Windows 10. The update is free, and users running Windows 10 have fewer issues with video playback.
See the system requirements page for more details.