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It seems that the upgrade of Telerik Control Panel fails due to missing previous version installer of Telerik Control Panel. To solve the issue you will need the msi installer used for installing the previous version. Could you check the exact version of the currently installer Telerik Control Panel at Programs and Features
? If the version is 13.1.425.0
, you could find it attached. Unzip it, right click it and choose Uninstall. This should help uninstalling the older version, so you could try again to install the latest version.
Let me know if that helps.