@sloeckle Well I can tell you that FOG doesn’t change any settings in the uefi menu, so that windows entry is probably from a previous install on that computer.

Now to your question about post download scripts. I have a tutorial that can be the starting point of your task.

The starting point could be here: https://forums.fogproject.org/topic/11126/using-fog-postinstall-scripts-for-windows-driver-injection-2017-ed

If you start looking in this section of the post fog.custominstall

In the code you will see that I key off the $osdi field. In this case I check to see if its one of the windows platforms. In your case you can use the same overall code flow/outline but switch case the linux code of 50. If you look a bit deeper into what is going on in the windows section we loop through the different disk partitions on the disk looking for the /Windows directory on the partition. If its found then we exit the loop with the proper partition number.

In your case you will loop through the partitions looking for /EFI or /efi If you find that directory (you could even be a bit more specific like /efi/boot then you know what partition number the efi partition is. Yo u could also look at the partitions by the partition type but that could be a bit misleading because not every uefi partition is of type efi. Searching for the boot file path may be a bit more universal. For uefi the path don’t change. You just need to be mindful of the case.

Once you have the identified partition then you can do the magic with the efibootmgr. You could be blindfully trusting and just replace the value in boot order 0000 or do a bit more coding to identify the values you don’t want to purge, or just insert your linux boot manager always at position 0 and set it to default. That will push all of the other entries down one position. I think that may be a messy approach especially if you reimage that target computer a number of times, but it would get the job done.