Parameter is missing a value ssrs 2008

Question

I have a parameter of integer datatype which is hidden. When i run the report, report gives me an error

Parameter X is missing a value

Answer 1

I had a similar issue where the default value as set by SSRS is (Null), I didn't need the parameter for my report however; I found it useful for testing to filter down the list so I kept it, I guess I could have deleted it in SSRS on the dataset config. but I changed it to =System.DBNull.Value (I guess this could be any expression) instead and that worked for me, so then I can still pass in a value if need be and also set Available values (had to make sure a NULL value was added to my dataset) if I then decide to unhide at a later date.