Upon logging into the Hive server, (hivemc.eu) I received a crash report. I tried other servers and received the same result. I attempt to log on with a windows 10 computer (Minecraft Ver 1.10.1) and also received the same result.
Environment
OS: Mac OS X (ver 10.11.3, arch x86_64)
Java: 1.8.0_74 (by Oracle Corporation)
Launcher: Minecraft Launcher 1.6.61 (bootstrap 100)
Minecraft: 1.10.1 (updated Wed Jun 22 03:14:48 MST 2016)
This is a duplicate of MC-103978.
The issue is caused by a modded server. Please do not create issues unless you are able to reproduce this on a 100% vanilla environment (Both client and server unmodded).