Any one else experiencing the problem stating : No dedicated servers are available for your version of halo 5 : guardians at this time. ?
There is a service alert out for this issue right now, as it is affecting multiple games. You can keep up to date here: https://support.xbox.com/en-us/xbox-live-status
There is also a thread you can follow in the Halo 5 Support forums
https://www.halowaypoint.com/en-us/forums/e0d9938206f04a598ce84f2c8cadce02/topics/343-response-can-t-access-halo-servers/645c3885-9167-4864-a8a3-ba234ca6ef04/posts