En familj Microsoft-produkter som gör det möjligt för användare att samla, ordna och återanvända anteckningar elektroniskt.
Finally managed to solve it!
I made an iTunes backup, reset the iPad.
Then restarted, and used the assistance offered, by using settings from my iPhone.
Installed and tried OneNote again: failed!!!
Did one more reset of the iPad.
Did no install from iPhone, just a new clear install.
Installed OneNote - it works!!!
I got a list of notebooks to open, and they all work.
After that I have NOT restored the backup via iTunes.
I chose to reinstall the few (about 20) apps I had on the iPad.
And it is still working.
Thank you all for your assistance!
.. / Jan