The import cannot be stopped, if the server is restarted then the error doesn´t disappear according to several posts in newsgroups.
So what to do? I checked and double-checked the SSP database and the values in the Profile_Stats, MIPObjects and MIPScheduleJob tables which all had values related to the Profile Import. But nothing that I did could solve the problem.
But then I remembered that the crawler application is based on the good old Indexing Service which means that the registry is also used to store settings. So after some digging I found the solution by changing a value in the registry for the crawler.
Open the registry editor. Browse to “HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office Server\12.0\Search\Applications”. Here you will find a key for each SSP in the farm. Drill down to "
I changed the number in the key “CrawlNumberInProgress” to “0xffffffff” and then restarted the “Office SharePoint Server Search” service for the settings to be applied.
The error message disappeared from “User Profiles and Properties” and I could start a new full import to the “User Profile Import”
Disclaimer: remember to backup your registry before making any changes. I am not responsible for your system damages because of any registry errors