From "OUT log" details sounds like there is a problem with the CF webserver connector.
What do you do to overcome the outage eg restart server, restart CF or restart IIS?
It would be nice to narrow down problem a bit more. Maybe there will be some interesting detail in ColdFusion8\runtime\lib\wsconfig\1\LogFiles\ jrun_iis6_wildcardYYMMDD.log file?
I want to suggest delete the old connector and rebuild it using WSCONFIG.EXE tool from ColdFusion8\runtime\bin however I expect when you unintalled CF8 you likely removed the IIS connector information then the subsequent install added the connector setup information again. Maybe you can comment on how you attached CF8 to IIS?
Sorry more questions than answers, Carl.