In WordPress version 5.0.1 there was a bug which would mean that uploading a CSV file could present the error “Sorry, This File Type Is Not Permitted for Security Reasons”. This was resolved after 5.0.3, but some users with special characters in their CSV files may still receive this error moving forward.
There is a few things to try if your CSV importer is presenting this error:
- Update your WordPress to the latest version.
- Try saving the file with UTF8 Encoding (as per this guide)
- If that doesn’t work, likely you have special characters causing WordPress to reject your CSV file. The current workaround is to install this plugin: https://wordpress.org/plugins/disable-real-mime-check/ and activate it. Your CSV imports will then probably ‘just work’. We recommend deactivating this plugin after importing your CSV file.