The Data Types Varchar And Varchar Are Incompatible In The Modulo Operator

I am trying to create a store procedure inside of SQL Management Studio console and I kept getting errors. Here's my store procedure.




Code Block
CREATE PROCEDURE [dbo].[sqlOutlookSearch]
-- Add the parameters for the stored procedure here
@OLIssueID int = NULL,
@searchString varchar(1000) = NULL
AS
BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;
-- Insert statements for procedure here
IF @OLIssueID <> 11111
SELECT * FROM [OLissue], [Outlook]
WHERE [OLissue].[issueID] = @OLIssueID AND [OLissue].[issueID] = [Outlook].[issueID] AND [Outlook].[contents] LIKE + ''%'' + @searchString + ''%''
ELSE
SELECT * FROM [Outlook]
WHERE [Outlook].[contents] LIKE + ''%'' + @searchString + ''%''
END




And the error I kept getting is:

Msg 402, Level 16, State 1, Procedure sqlOutlookSearch, Line 18

The data types varchar and varchar are incompatible in the modulo operator.

Msg 402, Level 16, State 1, Procedure sqlOutlookSearch, Line 21

The data types varchar and varchar are incompatible in the modulo operator.

Any help is appreciated.