In the manual from Microsoft for making a Windows PE cd based on Windows 7 there is an error resulting in unable to boot cd with error 0xc000000f The boot selection failed because a required device is inaccessible.

These are the correct steps.

1. open cmd and goto crogram FilesWindows AIKToolsPETools

2. copype.cmd <architecture> <destination>

where <architecture> can be x86, amd64, or ia64 and <destination> is a path to a local directory. For example, copype.cmd x86 c:winpe

The destination directory must not exist

3. Optional copy "crogram filesWindows AIKToolsx86imagex.exe" c:winpeiso

4. copy c:winpewinpe.wim C:winpeisosourcesboot.wim

5. Optional copy directories and files in de iso directory to be included in the iso

6. oscdimg -n -bc:winpeetfsboot.com c:winpeISO c:winpewinpe.iso

How can you boot the obtained winpe image on an itanium system?

Never had the privilege to work with itanium systems. I found a microsoft link for creating the winpe. They also mention what you have to do for a itanium system:

technet.microsoft.com/en-us/library/dd744537(WS.10).aspx

Creating a pe cd for Windows 8.1 has changed:

install Windows ADK Windows 8.1
start Deployment and Imaging Tools Environment
copype.cmd amd64 d:winpe
md d:winpedisc
mount Windows 8.1 64bits iso as g-drive
dism /mount-image /imagefile:gourcesinstall.wim /index:1 /mountdir:d:winpedisc /readonly
copy d:winpediscwindowssystem32recoverywinre.wim d:winpewinpe.wim
dism /unmount-image /mountdir:d:winpedisc /discard
rd d:winpedisc
unmount Windows 8.1 64bits iso
dism /mount-image /imagefile:d:winpewinpe.wim /index:1 /mountdir:d:winpemount

dism /image:d:winpemount /add-driver /driver:d:winpedrivers /recurse (if you want add additional drivers)

edit D:WinPEmountWindowsSystem32winpeshl.ini with notepad (run as administrator and remove readonly flag)

--------------------------------------------------------
[LaunchApps]
x:Windowssystem32startnet.cmd
--------------------------------------------------------

edit D:WinPEmountWindowsSystem32startnet.cmd with notepad (run as administrator)

--------------------------------------------------------
wpeinit
ipconfig
call %SYSTEMDRIVE%windowssystem32cmd.exe
--------------------------------------------------------

copy "Crogram Files (x86)Windows Kits8.1Assessment and Deployment KitDeployment Toolsamd64DISMimagex.exe" D:WinPEmountWindows

System32
dism /unmount-image /mountdir:d:winpemount /commit
copy d:winpewinpe.wim d:winpemediasourcesboot.wim /Y
makewinpemedia /iso d:winpe d:winPEbootcd.iso

MakeWinPEMedia /UFD d:winpe F: (to create a bootable usb disk)