I have seen this issue with bukkit before, but this is completely vanilla. Other players can break blocks and open doors but one user can no longer do this. The user can kill other players but that is it. This has just started happening today.
User is not an admin but can confirm other 'normal' users can play as normal.
Running vanilla 1.7.2 on Ubuntu. I have restarted the service and the user has rebooted their machine.
Is it possible that their user.dat file has some corruption?
Best Answer
There are two things in a vanilla server that can make a player completely unable to affect blocks. First, they may be inside the protected area around the current default spawn - since 1.7, the protected area's size can be changed in the server's properties file, and the default spawn area can be moved by the
setworldspawncommand. This would cause other non-op players to also not be able to affect the same blocks, though.The other likely culprit is that their Game Mode may have changed to Adventure mode. One of the main effects of Adventure mode is that player's cannot break blocks without the correct tools.
The player.dat files are, from what I can tell, stored in the same NBT format as almost all other Minecraft data. The format includes some heavy compression, so any damage or corruption would make the file completely unreadable, and Minecraft would most likely just spawn them in as if they were a brand new user.