Minecraft Crashes

Put the summary of the bug you're having here

What I expected to happen was...:
Stationary on a server.

What actually happened was...:
All players clients crash however there are no server error messages. The server itself stays online however the player's clients crash.

Steps to Reproduce:
1. Would love to know
2. how to
3. reproduce this bug.
4. Play on server for a while.