Problem solved!
I realized my FM2010 game (d:\pelit\FM2010) and the needed database (C:\Documents and Settings\Markku\My Documents\Sports Interactive\Football Manager 2010\editor data ) were in different locations.
You can use your FM2010 editor in order to find out where your database is located.
I´m having the same problem. When I´m trying to choose the database, FM2010 says there´s none to choose. I have tried all databases, but my FM2010 cannot find any from "Editor data" -folder. What seems to be the problem? My FM2010 version is updated, but still the error exists.