The Xbox 360 version will not micro-patch to the correct version, making it currently unplayable for everyone.
I am sure many of you know, but there is a small but dedicated community who still plays the Xbox 360 CoDs reguarly. For the last year, a serious issue has affected the Xbox 360 version where it will not micro-patch from version 24.0.0.0 to 24.23.14.0 (the version needed to play). This is the issue, the servers are not "down", no matter how long you sit in the menu it will not hotfix.
This has left the game completely broken and can not be played by anyone online, and I have been in discussion with Activsion support about getting it fixed but obviously it is not a high priority for them.
All I ask is that you go here and take 2 minutes of your time letting Activision know about the issue. The more of us there are, they will hopefully get it fixed.
https://support.activision.com/feedback-and-bug-report
Go here and file a bug report. Game is 'other', issue is connectivity. And then tell them that Black Ops 3 is not properly micro-patching to version 24.23.14.0 on the Xbox 360 version of the game.
For those curious the version the PS3 version works still.
If you want to go the extra mile, you can submit a ticket directly to Activsion support here to get in contact with a support rep:
https://support.activision.com/options
If you do submit a report, thank you for helping the community keep these older CoDs alive. At the bare minimum, I believe they should at least be given a proper shutdown instead of just breaking. So it just randomly breaking really annoyed me.