How can a Project Manager view completed tasks from the past three months in a task report that currently shows no results?

The correct approach for a Project Manager to view completed tasks from the past three months in a task report that currently shows no results is to modify the report filters to specify a different timeframe.

Changing the filters allows the Project Manager to precisely define what data should be included in the report. If the current report is not displaying any results, it might be due to the filters set to a time range that does not cover the past three months. By adjusting these filters to encompass the desired timeframe, the report will then pull in the completed tasks from that specific period. This is a fundamental feature in reporting tools, allowing users to tailor data visibility based on specific criteria.

The other methods suggested, such as adding a chart view, adjusting groupings, or increasing the date range, do not directly address the issue of the report showing no results. Adding a chart view simply visualizes data that's already being filtered; changing groupings would affect how the results are displayed but won't resolve the underlying filtering issue; and increasing the date range may include too much data or irrelevant data without specifically targeting the desired three-month period. Thus, modifying the report filters is the most effective way to ensure that the relevant tasks appear in the report.