How to set Message Rule in Outlook Express: Size Rule
This is a Hands On Tutoral. Click when indicated to get to the next step.
Your new message rule is all set. Click MOVE UP until the rule is at the very top of the list (if you have other rules set, you want this one to be first). Now click OK and the rule is set. Click OK for a summary of this tutorial in case you want to print it out.