Deleting the control panel msi from \ProgramData\Telerik\Installer\Downloads fixed the problem.
answered on 03 Mar 2017, 02:41 PM
We are sorry for the inconvenience.
In order to upgrade you need to uninstall the old Control Panel from your system fist (from Control Panel\All Control Panel Items\Programs and Features or using the MSI file in \ProgramData\Telerik\Installer\Downloads). We are aware this is not convenient and we will improve the upgrade workflow.
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