Anything for sysadmins!


PXE boot stopped working for WDS

After updating the Windows Deployment Service (WDS) server, it didn't seem to work anymore. The clients would try a PXE boot but couldn't find a TFTP server to get the boot image from. A colleague of mine found a great article about this problem.

It seems that when you have a single server that is running WDS and DNS, the DNS server binds to all ports in the WDS port range leaving the WDS server unable to respond to the clients.


  • TFTP downloads fail
  • Multicast downloads fail with a possible error code 2
  • When WDS tracing is enabled you will find one or more errors that resemble the following
    [2416] 16:01:36: [d:\w7rtm\base\ntsetup\opktools\wds\wdssrv\server\src\udpportrange.cpp:755] Expression: , Win32 Error=0x2<br/>[2416] 16:01:36: [d:\w7rtm\base\ntsetup\opktools\wds\wdssrv\server\src\regudpendpoint.cpp:192] Expression: , Win32 Error=0x2<br/>[2416] 16:01:36: [d:\w7rtm\base\ntsetup\opktools\wds\wdssrv\server\inc\RegEndpoint.h:354] Expression: , Win32 Error=0x2<br/>[2416] 16:01:36: [WDSTFTP][UDP][Ep=0] Registration Failed (rc=2)
  • When you run
    netstat –abn

    you'll find that 64001 to 65000 is displayed as being used

  • You've applied security update MS08-037: Vulnerabilities in DNS could allow spoofing


If you do not require WDS to use a static port range, you can configure WDS to dynamically query WinSock for available ports instead of using a port range. To do this you'll have to modify a registry key on the affected server.


Modify the key


and set it to 0. Then restart the Windows Deployment Services.

More information can be found here:


Room List Distribution Group

I just came across another Exchange 2010 surprise that I would like to share with you. When you are creating a new meeting and need a room to have the meeting in, you would normally add all the rooms and see which one is available. The guys behind Exchange 2010 came up with a solution for this. They introduced the Room List.

The room list is essentially a distribution group but with an added parameter. Unfortunately you can't create a Room List in the Exchange Management Console, so you'll have to use the Exchange Management Shell (PowerShell) for this. The command is quite straight forward.

New-DistributionGroup -Name "Meeting Rooms" –Members ConfRoom1,ConfRoom2,ConfRoom3,ConfRoom4 -RoomList

As you can see, the -RoomList parameter makes all the difference!

People no longer need to sift through the meeting rooms manually. They can now effectively use the Room Finder to find a suitable room.