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Read on for answers to common questions and issues when importing CSV files. For full file requirements, see Imports overview.

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Why can’t I start my import?

Vero validates your file and column mappings before an import can begin. Common reasons an import is blocked:
  • No columns mapped — you must map at least one column before importing.
  • Same property mapped to multiple columns — each Vero property can only be mapped once.
  • Missing required identifier — profile imports require an email or id column (or both device_token and device_type).
  • Missing event name — event imports require an event_name column.
  • Incomplete device mapping — if you map device_token, you must also map device_type, and vice versa.

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Why does my segment show a lower count than my import?

This usually comes down to one of two causes. 1. Duplicate rows Vero processes every row in a CSV, including duplicates, and shows the number of rows processed on the import. If two rows resolve to the same user, they update a single profile rather than creating two. The easiest way to check for duplicates is in your spreadsheet application before importing — for example, Excel’s Remove Duplicates tool. 2. Users without an email address By default, the id is the key field that identifies a user. If users are imported with an id but no email, their profiles are still created or updated — but they won’t appear in a segment, because a user needs a messageable address (such as email or a push token) to be segmented.

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Why were some rows rejected?

Individual rows can fail even when the import as a whole succeeds. Common causes:
  • Empty or missing identifier — the email or id value is blank for that row.
  • Invalid email format — the email value isn’t a valid email address.
  • Invalid date format — date values must be in ISO 8601 format (e.g. 2024-01-15T02:00:00+10:00).
  • Malformed row — the row has more or fewer fields than there are headers, usually caused by unescaped commas or newlines in a value.
The summary page after an import shows which rows failed so you can correct and re-import them.

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Why do I get an error after selecting a file to import?

This is usually a file format or encoding issue:
  • Wrong encoding — the file isn’t saved as UTF-8. Files saved with a different character set, such as Latin-1 or Windows-1252, will fail. Re-save the file as UTF-8 and try again.
  • Wrong delimiter — the file uses tabs or semicolons instead of commas. Make sure your file is a standard comma-separated CSV.
  • BOM (Byte Order Mark) — some editors add an invisible BOM character at the start of the file, which can corrupt the first column name. Re-save without BOM.
  • File too large — files must be 2 GB or smaller.
  • Empty file — the file has no data rows (only headers or completely empty).

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Which file formats can I import?

Only .csv files. If you’re working in Microsoft Excel or Apple Numbers, choose File > Save As… > CSV to export. .xls, .xlsx, and other formats are not accepted.

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How large can my file be?

Files must be 2 GB or smaller. Uploads have a 30-minute time limit, so very large files on a slow connection may time out.

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Need Help?

If you have any questions, reach out to us at support@getvero.com.