Hello Bernhard,
So I have been doing more testing to see if I can reproduce it. One thing that came to mind was to enforce XLS use during import. This resulted in the error you see about the OLE object. Which is correct because an XLSX file is not the same as an XLS file. An XLSX file is actually just a zipfile with files in it. You can even see that if you rename the file to .zip.
In the template you posted I saw that XLSX is set to use as file extension. Since your file has the correct extension, set this to
Take from file. Do you get the same error in that case?
(Why it does not call the Xlsx.php?)
RO CSVI does actually tell which reader to create in the file
administrator/components/com_csvi/helper/file/import/xls.php on line 73. On line 72 it gets the file extension to use. Perhaps you can check what value you get there. That should be xlsx.
I do wonder what you get on that line 73. Let me know what you find.
Kind regards,
RolandD
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