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    I have converted a large spreadsheet from another application to LibreOffice. Some rows are missing. What has happened?

    LibreOffice accepts sheets with a maximum size of 1,048,576 (220) rows.

    Sheets converted from another application which contain more than 1,048,576 rows are truncated.

    Note : If you cut your sheet in half before conversion and each half contains less than 1,048,576 rows, you will have no problems in converting them.

    See also What is the maximum number of cells, rows, columns and sheets in a LibreOffice spreadsheet?