After posting the last comment, I found the solution for this particular problem. The solution is to change from: .split('\.') to .split("\\.")   Also, I added a missing library from before, ooxml-schemas-1.4.jar. I tried to use the ConvertExcelToCSVProcessor before, but it is not possible for the specific excel files I need (in OLE2 format). That is why I need these POI libraries and why I want at least part of this guide to work for me.   It seems now is working after adding another library that was causing problems (the lack of it) commons-math3-3.6.1.jar. Let's see for how long this solution works.   Best Regards,   ... View more

Hi jenka13all, thanks for your reply. I am using exactly the same script as the OP. After changing to ExecuteGroovyScript, the processor is not even validated:                                                                     These are my settings for the processor:   I have no clue why this is happening. It looks like the script does not recognize the filename attribute or the '\' sign. I even installed Groovy on my computer, just to check if that was the problem. Can be because I am on Windows? I am not using docker or VM, it is Nifi purely on Windows 10.   Best Regards, ... View more

Hi,   I have been trying to follow your guide, but I am stuck in the groovy script part. I constantly get this error on the script part:       I have no idea how to fix it. I am feeding xls files after unpacking them from zip file.   Can I get some help? ... View more