we have two guests running different hosts.
after a power off or a reboot they will drop the connection after 30 sec.
to get it back up i have to disable the connections in windows (7 and 2012r2) and the re enable it. this lasts but some times, but have stopped again no reason i can find.
I have removed the nics form the guests, re installed the drivers and vm tools.
one is the e1000 nic the other is a vmxnet3.
tested the cable runs
others on the hosts do not have this problem.
the windows 7 was converted from a phy computer the 2012r2 was made from scratch in vmware. the 2012 r2 was the first to show problems days before the conversion on the windows 7 box.