Thank you that was very usefull,
Common Autodesk fix your installation software.
I installed process monitor to find what file is missing - see screenshots.
and indeed My Inventor 2025 gave me those error after installation:
Failed to initialize a component for aqccessing AutoCAD files.
Please try again.
Error 16
What was needed was to manually create file:
c:\Users\kleme\AppData\Roaming\Autodesk\Inventor 2025\RealDWGSettings.xml
And add this content to it:
<?xml version="1.0" encoding="utf-16" standalone="no" ?>
<RealDWGSettings InstallDirectory="C:\Program Files\Common Files\Autodesk Shared\RealDWG Shared 2025"></RealDWGSettings>

