I think we might have a fix on this. The other person I told you about that had this problem found that the new Lenovo BIOS is having a problem with the length of our PXE menu listing. To resolve the problem they disabled a lot of the lines they don’t use. Some of the lines can’t be disabled, but those that can are found in the registry on the PXE Rep. In the registry go to HKLM\Software\Intel\PXE\ProxyDHCP and change any value that starts with DisablePredefinedXXXX to have the data value of 1. The XXXX would be replaced with exactly what you want to have removed from the list (such as DosPE). The values are all already there and should be pretty self explanatory.
After the changes are made please stop and restart the LANDesk PXE service, try to PXE boot one of the affected devices, and let me know the results.
Level 2 Support Engineer - OS Deployment and Software Distribution