Hm, *that* is strange:
I Updated slime to be of version before 2004-7-7. worked. I Updated slime to be of version before 2004-7-8. worked. I Updated slime to be of version before 2004-7-14. worked. I Updated slime to be of version before 2004-7-21. worked. I Updated slime to be of version before 2004-7-22. worked. I Updated slime to be of version HEAD. works ...
Restarted Emacs. F5. works.
What the ... ?
Can you try debugging on the Lisp side? I don't know much about Windows, but maybe e.g. it would not let you bind port 4005 on the loopback interface if it is already bound to another interface - probably something else though.
BTW, you could abbreviate the second line to just:
(swank:create-server)
.. which was added ages ago but not publicised very well.
Okay, doing that and deleting fasl files now.
Very strange things happening here ...