When creating a milestone for one project, it throws an error "Validation error Project.Description should not be null".
Release: SAAS
Component : SAAS
The field "Description" was set to mandatory.
Whenever a field in Rally is set to mandatory then it becomes a required field for performing any actions.
When a field (Project-->Description) is set to mandatory at the Workspace UI level, all the projects in the workspace need to update the description field to avoid these Red-flair issues.