A SimpleGantt chart follows the table or range it is linked to and redraws within a moment of a change. When it does not, check these causes in order.
- The new rows are outside the linked range. A plain range covers exactly the cells you linked. Turn the data into an Excel table (Ctrl+T), click a cell inside it, then click Use current selection under Edit > Data and Apply. Tables grow with the chart automatically.
- The rows are filtered or hidden. With Follow filters on (the default), hidden rows are left out of the chart. Clear the filter, or turn Follow filters off under Edit > Data.
- The free limit is reached. The free version shows the first 10 tasks; a line above the chart says “Showing 10 of N tasks.” Tasks beyond the tenth do not appear until you add a license. A chart made in the free version keeps that limit after you add a key until you click Edit, then Apply.
- A column was deleted or the table was moved. The chart shows which column is missing (click Fix mapping), or says it is not linked to a plan: select the plan in the sheet, then click Link data.
- The chart is a copy or a picture. A pasted chart frame in Excel on the web can be a static picture. Delete it and insert SimpleGantt again. A picture placed with Place picture in sheet never updates by design.
- The add-in hangs. Open More options > Restart add-in on the chart, or close and reopen the workbook.
Rows with problems (missing dates, errors, end before start) are not a reason for a stale chart: they are listed under Issues.
Still stuck? Open More options > Diagnostics, click Copy diagnostics and send the details to support.