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CSV Upload Issues

Symptom: "CSV upload failed" or no file accepted​

  1. Confirm the file is a .csv, .xlsx, or .xls file under 20MB, with the column names in the first row.
  2. Re-save with UTF-8 encoding: in Excel, File → Save As → CSV UTF-8 (Comma delimited).
  3. Open in a plain text editor and confirm the first row is a header row with comma-separated values.
  4. Remove special characters from the filename.

Symptom: Columns not mapping correctly​

  1. On the Match your columns step, pick the correct field for each column (or Skip it). Fix anything listed above the table, such as a missing Address column or a field mapped twice.
  2. Avoid special characters, line breaks, or leading spaces in your column headers.
  3. Custom fields must be mapped explicitly to custom1-custom10 - they do not auto-map.
  4. Absentee fields use Custom 1 and Custom 2, so you can't map both.

Symptom: Some recipients missing after upload​

  1. Check your CSV for rows missing a street address - the Verify your data step marks those rows as skipped (unless you ticked Find mailing addresses from emails and they have an email).
  2. Remove blank trailing rows.
  3. After uploading, compare imported recipient count to your CSV row count (minus the header row).
  4. Switch on Undeliverable only on the list to find rows flagged by address verification.

Symptom: Addresses showing as invalid after upload​

  1. Switch on Undeliverable only on your mailing list to view flagged recipients. Each shows a warning with the reason.
  2. Click each flagged recipient and correct the address. Verification re-runs automatically on save. If you know an address is good, click Mark deliverable.
  3. If a valid address keeps failing, try reformatting the ZIP code and ensure the state abbreviation matches USPS standards.

Symptom: Verify your data shows scrambled or misaligned data​

  1. Open in a text editor and look for values with unescaped commas - wrap them in double quotes (e.g., "Smith, John").
  2. Confirm the delimiter is a comma (some Excel regional versions export semicolons).
  3. Re-export using CSV UTF-8 (Comma delimited) and try again.