I’ve been at it building my demo center the last couple of days, and I’ve had problems joining my Windows 2003 r2 x64 XenDesktop Controller to my domain. Well, I got it to work without the XenTools, but hey guess what, when installing them, I could not logon to the domain. Now, it turns out that this is by the 17th of April a known issue, here by this post, to help others out. I used the workaround to fix the problem, and did not install the new XenTools. Will try that 2, and update this article later on…

Here’s a part from the Known Issues forum over at the Citrix Support forum:

Various issues around networking connectivity from Windows guests with XenTools installed
There have been a number of reports around application-level networking failures within Windows guests. In all cases basic network connectivity between the systems can be confirmed, ie by ping. Some examples are the inability to join an AD domain when both the joining server and domain controller are XenServer VMs; and Windows VMs failing to access Windows Update.

We’ve made an updated version of the Windows XenTools available at https://bugtracker.vmd.citrix.com/browse/AT-277. If you experience the issues described here or similar issues please install these drivers in your Windows VMs and verify if the issues still exist.

IMPORTANT
If you used the workaround described in https://support.microsoft.com/kb/904946 to disable all checksum offloading be sure to REMOVE that workaround prior to verifying these drivers.

A couple things to note:

• The updated XenTools can be installed on top of the beta release drivers by running xensetup.exe.
• The EULA and version information of these drivers is incorrect – this is expected
• If you are connected to the VM via RDP when you install the updated XenTools your connection will break as the network driver is reinstalled. If that happens cancel the RDP retry to return to the “default” (VNC) console and complete the installation by rebooting the guest.
• The specific errors reported accessing Windows Update can indicate timeout errors. While least some of those cases would have been caused by the issues fixed in the updated version of XenTools, it’s also possible that other components between the virtual machine and Windows Update or WU itself may be involved. If you continue to see such issues please verify that similar systems are currently able to access Windows Update.

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