Thank you for contacting us and please, excuse the inconvenience.
From the attached screenshot I see that you try to uninstall RadControls for SharePoint 2010 Q2. I checked the source code for this version and you are right that the SharePoint is requirement, even for uninstalling. This was an omission in the installer, which is already fixed in the current version of the product. Unfortunately, the only proper way to uninstall the 2010 Q2 version of the product is to fit the launch condition, i.e. to have the SharePoint installed on the machine.
I hope this information will help you in solving this issue. Let me know if you need any further assistance.
the Telerik team
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