ZapBounce

ZapBounce and Google Drive

Google Drive accumulates contact lists as CSVs and spreadsheets that were exported once and never returned to a system. They are the shadow database most companies have.

Verification here is about the file, not about a platform, and Apps Script can do it without anything leaving Google's infrastructure except the addresses themselves.

The list in Drive is the one people actually send from

A CSV exported for a campaign in 2024 becomes the source for the campaign in 2026, because it is easier to find than the CRM export. Nobody has verified it since it was created.

Drive files also get copied and edited independently, so three versions of the same list exist with different edits and no record of which is current.

Verification on the file at least tells you which version has the most usable addresses, which is often the only way to decide.

How the data moves

  1. Use Apps Script with the Drive API

    Read the file, extract the address column, and submit it as a batch without downloading anything locally.

  2. Write results to a new file, not over the original

    Because somebody will want the original, and overwriting a shared file that three people have open is its own incident.

  3. Submit as one batch

    Apps Script has an execution time limit, so a per-row loop over a real list will stop partway.

  4. Compare versions by usable address count

    Where several copies of a list exist, the verification result is the most objective way to pick one.

Setting it up

  1. Write an Apps Script bound to a container or standalone, with the key in script properties.
  2. Use the Drive API to read the target file rather than requiring a download.
  3. Extract the address column and submit it as one batch.
  4. Collect results on a time-driven trigger.
  5. Write a new file with the verdicts rather than modifying the original.
  6. Where duplicates of a list exist, compare their usable address counts before choosing one.

Google Drive: common questions

Can I verify a file without downloading it?

Yes, with Apps Script reading through the Drive API. Nothing needs to reach a local machine.

Should I overwrite the original file?

No. Write a new one. Somebody has the original open and somebody else will want it unchanged.

Which copy of a list should I use?

Verify each and compare usable address counts. It is not proof of authority, and it is the most objective signal available.

Reference

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