VMware 5.5 - Windows Server 2012R2 losing network

If you use network card: e1000 or e1000e

You must install update:

https://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=2109922

Better options change NIC to: VMXNET3 (better and faster)
If you change NIC to VMXNET3, must install VMware tools (driver to NIC)