Please excuse us for the double post, but we have edited the intial one containsing the sensitive FTP data so it's not visible to the public anymore.
We have verified the license holder of the license supplied with this project has active subscription for our 5.1 version, so you can obtain the 5.1 license from your client.
In addition to the above, I believe there should have been no content changes since the experienced exception was preventing you from operating with the product. Downgrade is not an officially supported option, and we would strongly advise you against it. You can move on to fully upgrading your project to the 5.1 version and restore the project to it fully operable condition.
the Telerik team
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