Import backup failed - SQLIntegrityConstraintViolationException: Column 'parent_id' cannot be null

[Sascha Wolff]

Hello,

I made a backup with 6.15 and tried to import it in a fresh installation of 6.15, but I get this error:

SQLIntegrityConstraintViolationException: Column 'parent_id' cannot be null

I have no idea what to do now. I tried to import it during installation and after installation from admin menu, but neither works.

Do you have any ideas?

Cheers

Sascha