My exports used to work for months and have stopped working out of a sudden. I used to create print designs with a QR code smaller than 80px which keeps on throwing me the error that the export setting must either be set to print improved export or I should increase the placeholder size.
If I enable the print improved setting it prevents export overall due to the usage of a reserved string, stated as \. Although I searched everything, the Excel file as well as the Indesign file I was not able to find this character. I also searched for linebreaks.

https://ibb.co/Z8ZHbLw