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CSV import fails with 'invalid byte sequence' error

#8 Resolved
Susan L. 200 days ago

Trying to import a contact list exported from an older CRM and I get “invalid byte sequence, please save as UTF-8 and try again.” The file opens fine in Excel. What am I missing?

Andrew Anderson Staff 200 days ago

This almost always means the file is saved in an older Windows encoding (commonly Windows-1252 or Latin-1) rather than UTF-8 — Excel opens both without complaint, which is why it looks fine there. To fix it:

  • Open the CSV in a plain text editor (Notepad++, VS Code, or even TextEdit on Mac).
  • Use “Save As” / “Reopen with encoding” and explicitly choose UTF-8 (not UTF-8 with BOM, if your editor distinguishes).
  • Re-upload the re-saved file.

This is especially common with lists that have accented names or non-English addresses, since those are the characters that get mangled by the encoding mismatch.

Susan L. 199 days ago

That worked. A lot of the contacts did have accented last names, that makes sense now. Thanks!

This ticket has been resolved. Its author or SubsiMail staff can reopen it to reply further.

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