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Print at Jun 11, 2026, 12:36:03 AM

Posted by kadirumit at Jun 2, 2026, 4:56:42 PM

Save Error: java.lang.NullPointerException with 4+1 Mezzanine House Project
Hi everyone,

I've been working on a 4+1 detached house with a mezzanine floor, based on one of the demo houses. However, whenever I try to save my project, I encounter the java.lang.NullPointerException error shown in the attached screenshot.

I suspect this issue might be caused by specific objects or assets within the project. I am currently using Sweet Home 3D version 7.6.

To resolve this, I tried creating a new project and copying all the contents over, but the issue persists, and I still cannot save the file.

Does anyone know how I can fix this error without losing my multi-story design? Any help would be greatly appreciated.

Best regards,

ERROR: https://hizliresim.com/axcumj5

Posted by Puybaret at Jun 4, 2026, 8:35:37 AM

Re: Save Error: java.lang.NullPointerException with 4+1 Mezzanine House Project
To get more details about this error, run Sweet Home 3D from the command line with a command like:

"C:\Program files\Sweet Home 3D\SweetHome3D.exe" 2>log.txt

and post here the text of log.txt when you try to save.
----------------------------------------
Emmanuel Puybaret, Sweet Home 3D creator

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Jun 11, 2026, 12:36:03 AM