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The Setup > Rules menu shows default and custom business rules from every table. Rules which run on a time-based schedule are prefixed "TB." Without a paid license, time-based rules can only run once every 48 hours.
All time-based rules are disabled by default in the Standard Knowledgebase template. To enable time-based rules, go to Setup > Rules. Click the Edit icon next to the TB rule you want to enable. On the General tab of the rule dialogue, scroll down to select Yes under Rule is enabled.
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