GanttProject file corrupt

GanttProject Desktop Support
1

It seems my GanttProject file (.gan) got corrupted. When attempting to open, I get error message: ‘This document format is unsupported. The supported formats are: * GanttProject Documents (files with ‘gan’ extension) Content is not allowed in prolog.’ Using version 3.0.3005

Is there a way to fix the file, or do I have to restore a previous version from the backup?

2

Please share the file. Restoring from the backup is a good idea.

3

Please find the file attached
Mijn Planning 2025.gan (588,0 KB)

4

This is not a GanttProject file. It is basically a big chunk of zeroes.

5

Thank you for looking into it. I restored the file from the backup, it’s working again.