I ran into this issue whilst visiting a client this week, which I haven’t seen before. When the user tried to manually associate a project schedule with the workspace via Server Settings > Operational Policies > Project Workspaces , they would get this error:
After verifying the workspace was not linked to an existing project, I turned my attention to the the project workspace template that we were trying to associate. After a bit of searching around, it seems that the issue was caused by the site template used to create the project workspace being based on an existing site that was associated with a project schedule when it was saved.
In order to fix the issue, it was necessary to:
- Create a new Project site with the out of the box Project Workspace template;
- Reapply any customisations;
- Save the workspace into a new template;
- Create a site using the new template
- Associate the site with the schedule;
- Migrate the contents from the old site to the new one;
- Delete the old site.
Finally, the default project workspace template was updated to reflect the new fixed template using STSADM –o addtemplate and changing the Project Workspace Provisioning Settings.