Strange Character in SQL Database

I have a WPF C# application that saves and retrieves data in and out of a SQL Database. Everynow and then a strange character turns up in the DB. I'm assum开发者_如何学Cing it happens when incorrect data is passed into it, but it throws no error, and when I try to retrieve that row its like its not there, or doesn't exist.

I am unable to paste the character but it looks like an empty square.

Can anyone shed any light on this?

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Sounds like an encoding problem. Have a read here and see if you can deduce what's wrong afterwards: http://www.joelonsoftware.com/articles/Unicode.html