Error loading excel, preview still works

[SanderVW]

I am receiving the following error when I look at my dataset in the flow:

Failed to open Excel file, caused by: OfficeXmlFileException: The supplied data appears to be in the Office 2007+ XML. You are calling the part of POI that deals with OLE2 Office Documents. You need to call a different part of POI to process this data (eg XSSF instead of HSSF)

The weird thing is that it seems like there actually is no error with opening the file as the preview shows the data just fine, and the data is present too in datasets further down the line. It only gives this error when trying to show the sample. Does anybody know what might be the cause of this and how to solve it?

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Operating system used: Windows

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Operating system used: Windows

[CatalinaS]

Hi @SanderVW, 

You can solve this by going to the settings of this dataset and check the "XLSX" checkbox.

[SanderVW]

Hi @CatalinaS, this solved the issue for one of my datasets, thank you! However, some files I have are .xls files and for these this does not seem to work. Do you have any idea what could be a solution for these files? I can add that not all xls files are having issues, some are working just fine but I can see no discernable difference between these files and the files with problems.