All users are receiving this message after logging in and being disconnected after 1.5 seconds.
In a attempt to trouble shoot, i did the following
*Removed all addons
*Edited server properties and changed whitelist to false & removed the whitelist entirely, since that didn't work and i got the same results i have turned it back on.
Since one of my users is a relative on accessed there computer and when into appdata and deleted minecraft, and the .exe redownloaded it, had minecraft re-download the .jar's. and still no prevail.
As the admin i can log in fine, it is just other users, as my relative is on my network i considered the fact we have the same ip, and maybe there was a conflict (the addon session protect is not on) but it's occuring to people outside the network and even when only one of us is logged on.
*My server supports 20 users and we are at 1 (myself), so that's ruled out as well.