I have now removed the tag registrations from all my pages and the only tag registration left is in my web.config folder.
I have also emptied the Temporary Asp.net directories and checked there are no GAC entries for Telerik.
However I am still getting the "Ambiguous references" message as before.
Is it worth trying to upgrade the Telerik dlls or is there something else I can do to resolve the problem?
Extracts from web.config
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