For the Run / Debug configuration that you used for remote debugging, follow these steps:
- "Run β Debug Configurations ..."
- Select the remote config from the tree on the left
- Click the Source tab
- Click "Add ..."
- Follow the instructions in the wizard (add a project containing a debugged source).
If so, can you post a snapshot of Run Configuration ?
What I usually did with the Remote Debug startup configuration is Add Source as Java Projects on the Source tab in the Run / Remote Debug configuration. Thus, to add a project called so , I would do the following:

And when choosing a project, select two checkboxes:

The result is:

source share