I am the one as Administrator with ID 43
Have previously had both 62 and 42 but has changed all J25 contents and KK2 Items in the database from all ID62 and ID42. Yet when I change an article, I get the message:
JUser :: _load: Unable to load user with id: 42. Where comes it from and what do I have to change more?
Best regards

I found the solution in the User Group map.

Thank you

I would back up the site, and use phpmyadmin update statment to replace all of the author id's from the old to the new at one time.

Thank You for fast reply but I have already done this and now i have found the solution.

please share your solution with others

Yes of course!
I nave changed all users ID in J25 (Joomla) and in K2 Items from ID 42 and ID62 into 43.
I did it in my PHPMyAdmin.

I´m not new at Joomla but I´m new at K2 and have foud it interesting but it has a lot of parameters.
I´m goin to look at more tutorials to find out how to arrange artikels.

Thank you
Bassman