Stored procedure or function expects parameter which is not supplied

Question

I am trying to insert data into a SQL Server database by calling a stored procedure, but I am getting the error

Procedure or function \'SHOWuser\' ex

Answer 1

in my case, I was passing all the parameters but one of the parameter my code was passing a null value for string.

Eg: cmd.Parameters.AddWithValue("@userName", userName);

in the above case, if the data type of userName is string, I was passing userName as null.