Error Code 0x0000005c during WinPE load

[mojomatt]

Hi,

I'm using a first generation Hyper-V VM running on a Windows 2012R2 server and booting off of ipxe.iso (with ipxe.krn). I'm using wimboot v.2.5.2 to try and load WinPE. Here is the contents of the script I'm running using the chain command...

Code:

kernel http://x.x.x.x/winpe/wimboot  gui
initrd http://x.x.x.x/winpe/bcd        bcd
initrd http://x.x.x.x/winpe/boot.sdi        boot.sdi
initrd http://x.x.x.x/winpe/boot.wim       boot.wim
boot

I see each of these lines process o.k., then I see WinPE start to load with the blue windows logo in the middle of the screen. Next I get this error message...

Your PC needs to restart.
Please hold down the power button.
Error Code: 0x0000005C
Parameters:
<4 lines of parameters that I don't think will help troubleshoot so I'm not typing them>

I've tried with both WinPE 4.0 and WinPE 5.0 without luck.

If I boot from the WinPE .iso then it loads just fine.

If I don't add the gui parameter after wimboot in my script then I get this message:

Get parameters: C/H/S = 1024/255/63, drives = 1
Get disk type: sectors = 0xfff80040, type = 3
Extensions installation check
<and 2 more lines>

Any ideas why it's failing?