Excluding groups from tagging...or not

All the groups in a particular database (actually in all my databases) appear in blue, not yellow, indicating that they are excluded from tagging. However, if I get info on any of the groups, the Exclude from…tagging checkbox is disabled, not checked. What’s up with that? What might I have done to prevent all groups being used as tags, and why is the checkbox disabled?

You need to go into File>Database Properties… and uncheck ‘Exclude Groups From Tagging’. I believe that all databases were reset to exclude from tagging with the last update.