@ITCC Someone much more cleverer than me (from ANME) has worked out how to fix it and it is due to sysprep sealed images rather than Fog persay as Tom suggested. the Fix is to add the following to your sysprep SetupComplete.cmd file

for /f "tokens=2 delims={}" %%a in ('bcdedit /enum {bootmgr} /v ^| find "identifier"') do set prep-bcdid={%%a} bcdedit -set {current} device partition=c: bcdedit -set {current} osdevice partition=c: bcdedit -set {memdiag} device partition=\Device\HarddiskVolume1 bcdedit -set %prep-bcdid% device partition=c: