Import dates must remain real Excel date values and follow the sequence required by the selected data frequency. Incorrectly formatted or duplicate dates can cause the error Invalid file format. Certain months have been included multiple times.
Start with the correct sample
Download the sample file from the import page you plan to use. Keep its columns and cell formatting.
Prepare a monthly date sequence
- Paste the performance values into the data column.
- Keep the first cell in the Date column and enter the first required month as an Excel date.
- Select the cell, drag the fill handle down, and choose Fill Months.
Check the result
Verify that the dates are ordered, match the selected daily, monthly, or quarterly frequency, and contain no gaps or duplicate periods. Keep the date cells formatted like the sample.
Save the file as .xlsx and upload it through the same import page from which you downloaded the sample.
Continue your fund reporting workflow
Use this guidance as part of a controlled fund factsheet data import and validation workflow. Continue with Update or import fund data and Fund factsheet production software.