Need to greyout pull down menu in order management, order organizer form.

Need to greyout pull down menu in order management, order organizer form.

We have restriction to for salesperson, that they cannot open other salesman's salesorder. so we have default value in salesman name in their each saleperson while the login by their user and open the order organizer form. system show them their name as salesperson. so this personalization help to protect not to view other salesperson's sales orders. but user overidding such personalization by view pulldown menu. user going to view menu -> in record -> they search for last record when the cursor is salesperson column in form. system checking for last record so salesperson column gets empty so they