Title
Windows: Opening .gan files via file association or command line fails unless working directory is the installation directory
Description
Environment
- GanttProject: 3.3.3316
- Operating System: Windows Server 2025
- Environment: Remote Desktop Session Host (RDSH)
Problem
Opening a .gan file by double-clicking it in Windows Explorer does not open the project.
The same happens when launching GanttProject from the command line and passing a .gan file as an argument.
GanttProject starts (a process is visible in Task Manager), but the project itself is not opened and no error message is displayed.
Opening the exact same project through File → Open from within GanttProject works correctly.
Steps to Reproduce
- Install GanttProject 3.3.3316.
- Create or obtain a valid
.gan project file.
- Close all running GanttProject processes.
- Double-click the
.gan file.
Expected Behaviour
The project should open automatically.
Actual Behaviour
- GanttProject starts.
- The project is not opened.
- No error message is displayed.
Additional Findings
The issue can also be reproduced from the command line.
Does not work:
"C:\Program Files\GanttProject-3.3\GanttProject-3.3.exe" "C:\Temp\Test.gan"
Works:
cd /d "C:\Program Files\GanttProject-3.3"
GanttProject-3.3.exe "C:\Temp\Test.gan"
Opening the project through File → Open from within GanttProject also works.
Additional Observation
When opening a .gan file directly (double-click or command line), an app\plugins folder is automatically created next to the project file.
Example:
This folder is not created when opening the same project through File → Open inside GanttProject.
This behaviour may indicate that the application is using a different working directory when launched with a project file argument.
Workaround
A workaround was implemented by launching GanttProject through a VBScript wrapper which first sets the working directory to the installation directory. After doing so, opening .gan files works correctly.
Notes
The issue was reproduced multiple times and is not related to:
- File association configuration
- Corrupt project files
- UNC paths
- User permissions
The same .gan file opens correctly through File → Open once GanttProject is already running.
Title
Windows: Opening
.ganfiles via file association or command line fails unless working directory is the installation directoryDescription
Environment
Problem
Opening a
.ganfile by double-clicking it in Windows Explorer does not open the project.The same happens when launching GanttProject from the command line and passing a
.ganfile as an argument.GanttProject starts (a process is visible in Task Manager), but the project itself is not opened and no error message is displayed.
Opening the exact same project through File → Open from within GanttProject works correctly.
Steps to Reproduce
.ganproject file..ganfile.Expected Behaviour
The project should open automatically.
Actual Behaviour
Additional Findings
The issue can also be reproduced from the command line.
Does not work:
Works:
Opening the project through File → Open from within GanttProject also works.
Additional Observation
When opening a
.ganfile directly (double-click or command line), anapp\pluginsfolder is automatically created next to the project file.Example:
This folder is not created when opening the same project through File → Open inside GanttProject.
This behaviour may indicate that the application is using a different working directory when launched with a project file argument.
Workaround
A workaround was implemented by launching GanttProject through a VBScript wrapper which first sets the working directory to the installation directory. After doing so, opening .gan files works correctly.
Notes
The issue was reproduced multiple times and is not related to:
The same
.ganfile opens correctly through File → Open once GanttProject is already running.