Anybody had a problem trying to get a gamertag but it hasn't been associated with an account ?

and to add to the above, if a tag looks to not be in use but still cant get it then it may be in use but on another service, also accounts that have been banned in the past will have the name locked out too.

That is because you aren't lookingnhard enough

If you are trying to find an unique make but you are getting hashtag instead that is because it is taken

You gotta remember that gamertag is the same as GamerTag or gamer Tag in the million or so different variations

So yes to find a gamertag you MUST have the exact spelling you will meter find the exact combination

The only way to get a unique gamertag is to have a unique spelling like symbols or character replacement

I or anybody else I know hasn't had this problem.

The best thing to do is to talk to xbox support by going to support.xbox.com/contact-us and give them the old gamertag and if they can verify the ownership of the account they can tell him the email associated with that gamertag.

it is possible that if the account hasn't been used for a while that they did close the account out.

Unfortunately, this feature hasn't been implemented on the Xbox One console yet. You can only change the MS account associated with a gamertag through an Xbox 360 console. This should change in a future update.