I have 3 VMWare servers, added the 3 servers and monitoring were normal. Today one of the servers that the information appearing disk, CPU and memory blank. OpM version 10200

I tested the credential and is working. What can it be? 

And no VMPerformance Monitor is working.

EDIT: Graphical and it gets moved, is not aligned properly, as you can see in print.

I've added the device and deletes, and the error persists!