i keep getting spammed by money email, investment type mails, but they keep coming from different email addy, how can i stop them all at once??

Outlook express has some built in tools that help a little. Go to: tools>blocked senders list...and you can block the ones you want. Your ISP should have a spam blocking program, alot of them contract that to someone else. Check with your ISP to find out if they have it and how to access it. But you can block most of it before it ever gets to your machine with programs like "Mailwasher", available here:
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There are a number of free programs here that work well, and you can configure them to filter out most of your unwanted mail. You can also set up a white list, and a blacklist to let the ones you want through, or get the ones that slip thru occasionally.