Apply to vhd (Windows 8.1) fails

Hi,

I 'm trying to apply windows 8.1 install.wim to a vhd but get the following error (on a Windows 7 x64, have no windows 8.1 yet -that's why I'm creating this vhd ... or should I boot into a winpe 8.1?):

2014-11-10 15:48:22, Error                 DISM   DISM WIM Provider: PID=5588 TID=6880 base\ntsetup\opktools\dism\providers\wimprovider\dll\wimmanager.cpp:1095 - CWimManager::Apply(hr:0x80070057)
2014-11-10 15:48:22, Error                 DISM   DISM WIM Provider: PID=5588 TID=6880 base\ntsetup\opktools\dism\providers\wimprovider\dll\wimmanager.cpp:4601 - CWimManager::InternalCmdApply(hr:0x80070057)
2014-11-10 15:48:22, Error                 DISM   DISM WIM Provider: PID=5588 TID=6880 Error executing command - CWimManager::InternalExecuteCmd(hr:0x80070057)
2014-11-10 15:48:22, Error                 DISM   DISM WIM Provider: PID=5588 TID=6880 base\ntsetup\opktools\dism\providers\wimprovider\dll\wimmanager.cpp:2273 - CWimManager::ExecuteCmdLine(hr:0x80070057)
2014-11-10 15:48:22, Error                 DISM   DISM.EXE: WimManager processed the command line but failed. HRESULT=80070057

This is what I did:

   DISKPART> create vdisk file=d:\w8.1.vhdx maximum=25600 type=expandable
    select vdisk file=d:\w8.1.vhdx
    attach vdisk
    create partition primary
    assign letter=W
    format quick label=w8.1.vhdx

Tried to convert mbr of disk, tried vhd (vhdx is for windows 8.1/2012 only, right) but I'm out of options now.
ADK is version 8.1.

Please advise.
J.

Jan Hoedt