Scenario: A fatclient/desktop with Windows 10, RES VDX 10.1 Plugin, Ivanti (RES) Workspace Control 10.2.500 and the VMWare Horizon 4.5.0 client installed. Connecting to a Windows 10 VMWare Horizon 7 VDI that runs RES VDX 10.1 Agent and Ivanti (RES) Workspace Control 10.2.500. There is no RES VDX licensing server available, but the RES VDX licenses are available from within the Workspace Manager database. VDX works, but after some time a message appears that the grace period for VDX has expired, and VDX stops working.
When you check the VDX agent on the VDI, you see that it hasn’t been able to aquire a license for VDX.
In our case, we’re running an extensive script to optimise our VDI. This script has been scavenged from several sources like the VMware OS Optimization Tool and some blogs. Somewhere along the road, we decided that most of the tweaks we do for our VDI, could benefit the fatclient/desktops as well, so during the build of these systems, the script will run as well. Of course we’ve re-enabled or disabled stuff that is obviously needed for a system with spindles, like the disk defragmenter service, but most tweaks we were happy to run on these systems.
Since VDX wouldn’t aquire a license, the first thing we did, was blame RES. When that didn’t work, we started looking for other culprits. We found quite soon that our old Windows 7 fatclients could successfully aquire a VDX license when connecting to the Windows 10 VDI, so since the effect of our script on the fatclients/desktops wasn’t really known, i decided to turn it off, and tested again; VDX could aquire a license in the new scenario.
As the script was over 200 lines long, it took some guesswork to find out the culprit, but by a stroke of good guesswork, we found the fault:
DisableTaskOffload was set to 1. This was done, probably, because using offloading for networktraffic, requires a physical networkcard. No problem for our VDI, but it appears that either RES VDX uses this function somehow, or when a pshysical NIC is actually present, Windows 10 requires task offloading to work. Anyway, removing the registry value altogether on the fatclient fixed our issues. We decided to remove it for all platforms: let Windows figure this one out.