Locating documents and sharing them with others within Microsoft Teams channels or chats
Planner itself does not import tasks directly from an Excel file, and the error about the file being too big comes from the upload limits of the service or connector being used (for example, Power Automate or the underlying SharePoint/Teams file storage).
To work around this:
- Reduce the Excel file size so it can be uploaded/processed:
- Remove unnecessary sheets, images, and formatting.
- Split the workbook into multiple smaller files (for example, by date range or project segment) and import each part separately.
- Follow the guidance to reduce the workbook's file size and then retry the import/flow.
- If the issue is viewing or handling the file in Teams/SharePoint:
- If the workbook exceeds the file size limit for the Microsoft 365 subscription, it cannot be viewed in the browser. Download it and open it in the desktop Excel app instead, then reduce/split it and re-upload.
- If using Power Automate to create Planner tasks from Excel:
- Point the flow at a smaller Excel file (after splitting or reducing it).
- Run the flow multiple times, once per smaller file, until all rows are imported as tasks.
Planner has no built-in “upload Excel to Planner” feature; all imports rely on Excel files that must stay within the size limits of the connected services (Teams/SharePoint/OneDrive/Power Automate). Reducing or splitting the workbook is required when the “file too big” error appears.
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