When Beacon returns an internal error message it is unable to read your file correctly. This is likely due to a formatting issue caused by the program you are using. We most often observe this when saving a .CSV using Excel.
When Excel saves a "CSV UTF-8" file, it often saves it as UTF-8 with a BOM (Byte Order Mark) — a hidden 3-byte sequence (EF BB BF) prepended to the start of the file. This BOM can make it hard for systems trying to cleanly read and import the data in the .CSV document.
To fix this issue we recommend the following:
If Working on a Mac: We recommend opening your file in Numbers (if working on a Mac) and resaving it/exporting it as a .CSV. Numbers tends to save the .CSV cleanly without the BOM.
Open the CSV in Numbers → File → Export To → Select CSV → Text Encoding: Unicode (UTF-8) → Save
If Working on a PC: We recommend opening your file in Notepad, and resaving it as a .CSV from that program.
Open the CSV in Notepad → File → Save As → change the Encoding dropdown from "UTF-8 BOM" to "UTF-8" → Save. Done.
These programs export a clean UTF-8 file without a BOM.
Other programs, which may help include:
VS Code (free) — Open the file, click the encoding label in the bottom-right status bar (it'll say "UTF-8 with BOM"), select "Save with Encoding," and choose "UTF-8."
LibreOffice Calc (free) — A full Numbers equivalent for Windows. It exports clean UTF-8 CSVs without a BOM by default, and most customers find it intuitive since it looks like Excel.