SCCM, Dell Optiplex 7060 "Unable to download PXE variable file. Exit code=14"

Question

Ok, so I am trying to PXE boot this machine over IPv4, UEFI mode, Secure Boot enabled. I get the following messages:

"Failed to download PXE variable file after retrials. Exit code=14. PxeGetPxeData failed with 0x8004016c."

"RegOpenKeyExWis unsuccessful for Software\Microsoft\SMS\Task Sequence GetTsRegValue() is unsuccessful. 0x80070002."

I also try to ping the server and get:

"PING: transmit failed. General failure." Packets: Sent = 4, Received = 0, Last = 4 (100% lost)"

I know it is seeing the server because it gets the IP address and loads the files. When it gets to the task sequence it starts to run then goes to a blank screen.

Any information to help resolve this issue will be helpful.