Enable Legacy Boot Mode on Windows 8 Pre-Installed Device

Apparently Microsoft requires OEM suppliers of Windows 8 systems to set the BIOS (actually UFEI now) to Secure Boot by default. This and another setting can prevent booting from CD/DVD drives and USB devices and also prevent Windows 7 (or older) network deployments from succeeding.

To enable smooth Windows 7 (or older) installations or booting from various boot disks, e.g. for disk imaging or repartitioning, etc, you will need to do the following:

1. Enter the BIOS/UEFI using whatever method the hardware vendor provides for this
2. Look for the Secure Boot option and disable this
3. Look for Legacy Boot or CSM (Compatibility Support Module) and enable this

In some cases, you will need to revert these settings to enable Windows 8 to install and/or boot.

Windows Deployment Server Multicast Is VERY Slow

If WDS multicast deployment is creeping VERY slowy, you probably have switches that are not able to fragment packets the way Microsoft expects.


To change WDS so it does not send fragmented packets do the following

Windows Server 2008R2
Set the following registry key and restart the WDSService
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WDSServer\Providers\WDSMC\Protocol
Name: ApBlockSize
Value type: REG_DWORD
Value data: 1385 decimal

Windows Server 2008
Windows Server 2008 uses network profiles to control the setttings.  Do the following to configure it to not send fragmented packets

1. Click Start, Run, WdsMgmt.msc
2. Right click the WDS server and choose properties
3. Choose the network settings tab
4. Change the network profile to custom

Set the following registry key and restart the WDSService
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WDSServer\Providers\WDSMC\Profiles\Custom
Name: ApBlockSize
Value type: REG_DWORD
Value data: 1385 decimal

If this allows the multicast transmission to complete you can then modify the TpCacheSize registry key below to increase the performance.  If you decrease ApBlockSize without increasing TpCacheSize then overall performance will decrease. Basically ApBlockSize * TpCacheSize = the maximum bandwidth that can be achieved. Increase it from 1190.

Windows Server 2008 R2
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WDSServer\Providers\WDSMC\Protocol
Name: TpCacheSize
Value type: REG_DWORD
Value data: 3145 decimal

Windows Server 2008
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WDSServer\Providers\WDSMC\Profiles\Custom
Name: TpCacheSize
Value type: REG_DWORD
Value data: 3145 decimal
Restart the WDSServer service after setting this registry key.  After setting this run a deployment to verify it completes and take note of the time to download the image.  Then increase this value in increments until it fails or reaches 7550.

If you have to disable IP fragmentation to get multicast working then this may be indicative of low-end switching/routing hardware that perhaps does not support fragmentation efficiently or does not support multicast efficiently (IGMP/MLD snooping etc.).  Multicast can be demanding on a network so it can expose problems or issues in network infrastructure that were unknown until multicast was setup. 

References
http://support.microsoft.com/kb/2582106

Windows Deployment Server's Message from Administrator

On your WDS server type the following at a Command Prompt:

WDSUtil /set-server /AutoAddPolicy /Message:"To contact your network administrator, please dial 123-4567“

If your message is too long (I haven't tested how long), it will fail.

References:
http://trycatch.be/blogs/roggenk/archive/2010/06/23/message-from-administrator-in-wds-windows-deployment-services.aspx