Question

I would like to know if in SQL is it possible to return a varchar value from a stored procedure, most of the examples I have seen the return value is an int

Example within a proc

declare @ErrorMessage varchar(255) if @TestFlag = 0 set @ErrorMessage = 'Test' 
return @ErrorMessage 

calling on asp.net
Updated:

Error:
Conversion failed when converting the varchar value ‘Development’ to data type int.

   using (DataContextDataContext dc = conn.GetContext())
{
    string serverName = ""
    var result = dc.spGetServerName(ref serverName);                    
    return result.ToString();

}

Answer 1

No, you can’t return anything but an int using the RETURN statement.
You’d need to use OUTPUT parameters instead. They are more flexible.

e.g.

CREATE PROCEDURE dbo.ExampleSproc 
    @OutParam VARCHAR(10) OUTPUT
AS
SET @OutParam = 'Test'
...
GO

Update:
For an example on how to retrieve the output param, see this article.