*** Updated post for iTunes 12.2 **
Apple released iTunes 12.1 for Windows 64-bit in April. Although labelled as a minor upgrade, under the covers, Apple has made a major change to the distribution for 64-bit Windows. iTunes 12.2 has just been released and shares the same issue.
The 12.x upgrade has a major flaw that it has removed support for importing / playing videos for computers with 'old' (in Apple's terms) video cards. This seems to include virtual machines running iTunes. It also affects iHomeServer when iHomeServer is running iTunes in the background as a service (because the Windows service session uses a virtual graphics card rather than your real hardware one).
Therefore, if you are using iHomeServer to run iTunes in the background on a 64-bit operating system such as Windows Server 2012, Windows Home Server 2011, or Windows 7 64-bit, you may find that iHomeServer is no longer able to add video files to your iTunes library. You can verify this is because of the upgrade by looking in the 'Messages' window of iHomeServer. You may see a message similar to the following (note this message is coming from iTunes, not from iHomeServer):
Video playback is not supported on this computer.
Fortunately, for the time being, there is a quick resolution to this. Apple has provided an alternative download package for iTunes 12.x that continues to support 'old' graphics cards. We have started testing this with iHomeServer running iTunes in the background and it behaves as before, correctly importing movie files. The link for this download is here:
We will continue to work to find solutions for iHomeServer, and hope that Apple expands its compatibility of 64-bit iTunes version to remove this major constraint.
In the meantime, we ask users not to upgrade to future versions of iTunes until we have verified compatibility or identified similar workarounds.