Hi Robert,
I must admit I don't know why Numbers is displaying that message.
Numbers allows up to 255 columns and up to 65,535 rows. Numbers will slow down well before those limits.
Normally, Numbers (when importing an Excel document that exceeds those limits) will truncate (chop off and ignore) columns and rows outside those limits.
Do the Excel sheets have blank columns and blank rows between blocks of data? Are they necessary?
Robert Lesperance wrote:
Even if empty, I erased the content of column 221 to 16239 and tried to import it once again. I still have the same error.
Try deleting the rows below the data, even if they look blank. There could be invisible characters such as spaces.
One thing you could try is to select and copy only that part of the Excel sheet that you want, and paste into a Numbers table.
Please call back with your findings.
Regards,
Ian.