text: Q:
  
  SSRS date conversion works on preview but not on deployment server
  
  OK, am a bit confused, I have an expression that turns the date into a UK format and with 3 years taken away, the expression is:
  
  =cdate(format(DateAdd(DateInterval.Year, -3, now),"dd/MM/yyyy"))
  
  This works happily when previewing the SSRS report in VS2015, however when I run it on the deployment server I get this message:
  The DefaultValue expression for the report parameter ‘StartDate’ contains an error: Conversion from string "20/10/2013" to type 'Date' is not valid. (rsRuntimeErrorInExpression)
  What is wrong with the expression to bring this error? and surely the same error should appear in the preview to?
  Thanks
  
  A:
  
  This will be due to regionalisation differences between your dev environment and your server.  One of them will be dd/MM/yyyy and the other MM/dd/yyyy.  Where possible pass date types or unambiguous string formats such as yyyy/MM/dd.
  
  