That is correct, you only need to have the Run-time version of Test Studio installed on the execution machine, but please ensure that all machines are running the same version. If you haven't done so already, please check this KB article
on "Resolve Common Scheduling Issues" and follow the troubleshooting steps described there.
Also, consider the option to upgrade to our latest internal build (2011.2.1209). It contains changes in the implementation for the Scheduling feature. You can download it from your Telerik account here: Public URL
If you continue to have difficulty with this, please export the Scheduling Log contents (to Excel or Text file) and send it to us. It's located here by default:
C:\Program Files (x86)\Telerik\Test Studio 2011.2\Bin\Telerik.TestStudio.Scheduling.Log.
Hope to hear from you soon!
the Telerik team
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