Note that the message of the exception is not related to the Telerik controls, because they do not use an assembly called DISABLED
Most probably the requested assembly is no longer available on your machine, so you need to locate its reference (it could be in web.config, in a page or in a custom web part) and remove it. If the assembly reference is in web.config, it is possible that SharePoint cached it. In this case the reference will be added in web.config each time the file is updated, for example when a web part is deployed.
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