This is related to the Paging File.
One of the server in the Main Office sent a message that The Paging File has reached 90%
I checked the Virtual Memory (at that server) is 1.5 RAM
My Question: How to know the Causes of it and how to troubleshoot it? (Per my understanding: If it is related to the CPU Spike, I can use the Task Manager>Processess> then watch which processes that cause the CPU Spike, then Google it; and the Paging file is different with the CPU Spike)