Yesterday we set up an Windows Server 2008 R2 on a HP DL380 G7 to run Symantec Altiris for deployment. However, whatever we did, it just didn’t work! The computers couldn’t PXE-boot. After a lot of googling and testing, we finally found the problem: On the physical NICs, you need to turn of Checksum Offload, Large Send Offload and TCP Connection Offload. It’s possible that you don’t need to turn off all of these services, I didn’t have the time to try all possible modes with these options. If you have, please feel free to write about your findings in a comment below.