Size property has an invalid size of 0

You need to define a length when specifying the varchar parameter:

SqlParameter job1 = cmd2.Parameters.Add("@job", SqlDbType.VarChar, 50);

You should use the same length as defined in your SQL Server stored procedure.

And btw: if your stored procedure also has no length defined (something like @job VARCHAR OUTPUT) – then you’ve defined a varchar string of 1 character length ……