Cruiser, unless you do what I said in my last post re: only giving out your new (Yahoo) address to friends, family and for personal use such as solicitor, bank, NHS, GP surgery, council services etc. - Trusted users and so on - Paras 3, 4 & 5,.you are going to hit the same problem again and again.
Go have a good look at a broad selection of what you say are the spam emails in Outlook and GMX and see which addresses they are being sent "From" and then mark them as Junk or Spam.
Spam mainly gets in by many routes; such as web crawlers, buying lists of known addresses, speculatively using name@domain guesses then they "broadcast" in the hope of sucking people in. They can even steal contacts lists and raid the inboxes from anyone you have ever emailed.
Tips for your new email address:
Don't use your real name!
If you are going to use Cruiser or similar add some random characters behind it e.g.
CruiserLt39Ir0@xxxxxxxxx.com (makes it hard to guess)
Send an individual email to family and friends warning them to look out for you new address, but don't include it in the email.
For example: From: (your old address) To: Whoever. Subject: A change of plan:
"Look out for my new e-address. It will be 'Me' followed by some random characters at my new provider." Please do not give it to anyone else once received. Thanks.