I can't believe that this problem caused me to fustrate and despress for hours. but the good thing is that eventually I got the problem resolved.
So here's what happened: I have VMWare Workstation 10 installed on a new machine with a static IP address, and I use it as a closet server. If the VM is a Windows 7, I can use Microsoft Remote Desktop to access it. But if the VM is a Windows 8 or Windows Sever 2012 R2 VM, then the remote desktop doesn't work.
I was confused and kept trying different options. And then I found that if I turned off Firewall, the connection works.
Eventually I found out that all I need to do is change Firewall setting to let "Public" access of remote desktop "on". It seems like that the VM on my closet machine things that access that VM thru remote desktop on another machine in the same network is still consider "public" because of how VMWare route virtual network packet.
At least I got it working.