Converting varchar to datetime

Hi,

I've created a report that works perfectly in Visual Studio when I preview it, but once deployed I get the error: -

Having checked my dataset Claims, I noticed this contained a column Claim_Date that although containing a date (UK format e.g. 31/10/16) it was actually set to Varchar. I am guessing this may be my issue?

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I tried to use convert on the column in question, but when running the report I got the same error. Has anyone had a similar issue and how do I get around this?

From some reading, I may need to cast to datetime, but not entirely sure where to start with that one.

Any advice appreciated.

Thanks

Glenn