Do you get this error when you export your attendee data?
Does the file automatically open in another web browser, as shown below?
When exporting a .csv file using Safari, you may experience an issue where the file is displayed within the browser instead of downloading locally to your computer.
To download the file, please follow these steps:
Click the Export link
Once the file is displayed in your Safari browser, go to File > Save As…
In the next prompt, change Format to “Page Source”
Change the file name as needed and add .csv as the file extension in the file name
Please note: this only happens when you use the Safari browser. You can also export the file in Google Chrome or another web browser.