From the navigation bar, click Administration.From the Settings page under App Setup and Dashboards, click Reviews. The Review Processes page opens.
In the list beside a review process, click . The Review dashboard opens.
Click the Launched tab.
Click (beside the search box) and then click Remind Key Reviewers.
On the confirmation pop-up, click Remind. All key reviewers in this review process who have not declined or submitted a key review receives a reminder email.