Ran into some issues when upgrading or installing a new 2019 server. Some of the problems are consistent, others may or may not happen.
Network – upgrade.
IPV4 settings are transferred but IPV4 protocol is not enabled on the NIC, only IPV6 is enabled. You have to manually enable IPV4 then it will work.
If it previously had remote desktop access, the firewall will block it. However, the firewall will show access is allowed when looking at permitted apps rather than advanced security. Run admin command line to enable remote desktop thru the firewall.
Enable-NetFirewallRule -DisplayGroup “Remote Desktop”
File and Printer sharing for Microsoft networks is turned off on the NIC. If the machine was a print server or file server, it will not function as such. All other file and print settings are retained in the upgrade so you only need to check the box and function is restored.
In a new install, the GUI activation for a MAK is broken and always returns an invalid key error. Probably the same in upgrade. You have to enter the key from the admin command console or Powershell using:
slmgr – ipk XXXXX-XXXXX-XXXXX-XXXXX-XXXXX
Hyper-v. The external connected virtual switches are changed to internal connection. I just created a new virtual switch with external connection and replaced the old ones.
Hyper-v. Virtual machines may not boot. Failing after a series of short multiple attempts. The problem is known and the work around is to change the MAC address on the virtual machine. If it’s dynamic, switch to static AND change the MAC address. Just 1 digit is enough. You can change back later.
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