Hello Ken,
Could you specify if you were able to test the provided workaround and whether it helped on the production? Generally the issue should be faced regardless of the deployment environment, since you mentioned that the version is the same. Could you double check if this is correct? You could be sure if you view the source of the page and search for
<!-- 2013.2.717.45 -->.
However, the previews implementation of the event attachment is as follows:
You could try to add this implementation in the dev/test environment and try to reproduce the problem.
Regards,
Nencho
Telerik
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