as told earlier in this news group - with some pain I had downgraded to sp3.
As expected it works fine with sp3 only at 1st glance.
Network connections to other computers may slow down 50x  and only PC reset
can help against it.
Outlook archives whenever and what it wants, overriding evrky folder
settings for autoarchive period.
And not to mention a crash once a week.
And there doesn't seem to be noone who could provide any help when things go
wrong.

robert