Did a side by side migration from 9.5SP2 to 9.6SP2. PXE rep was set up using our DHCP server. Once all the clients were moved to the new 9.6 server I started working on getting PXE set up. I removed the 9.5 PXE rep from the DHCP server, upgraded the agent on that server to 9.6, then redeployed the PXE rep.
Booting to PXE I get mixed errors.
If I reboot a computer ten times, I get PXE-E55 half the time. If I do manage to get past this point, I get error PXE-E78 sometimes, and sometimes it successfully boots into Provisioning. It may boot successfully the first time, or the tenth time. I have tried removing and redeploying PXE to the server, tried rebooting the server, tried playing around with the options as described in several community articles. Network guru looking at it as well, doesn't make sense to either of us, since it's not consistent.