Bulk Migration CSV Format

Use this format with Bulk Import. The file contains source mailbox passwords, so create it in a secure location and delete it when the migration is complete. Do not attach it to a support ticket or store it in a repository.

Download the simple or full template from Import > Bulk Import if you prefer to start with a file TrekMail has generated.

Simple format: three columns

Use this when all source mailboxes use the same IMAP server. Choose the provider and enter the shared server settings in the Bulk Import form.

source_email,source_password,destination_email
alice@old-example.com,app-password-for-alice,alice@yourdomain.com
bob@old-example.com,password-for-bob,bob@yourdomain.com

No destination password is needed.

Full format: six columns

Use this when source mailboxes use different IMAP hosts. Turn on Each row has its own server settings in the form before previewing the file.

source_email,source_password,destination_email,source_host,source_port,source_security
alice@gmail.com,app-password-for-alice,alice@yourdomain.com,imap.gmail.com,993,ssl
bob@old-example.com,password-for-bob,bob@yourdomain.com,mail.old-example.com,993,ssl

Ask the source provider for the host, port, and security setting. Prefer its secure IMAP option. Do not choose none merely to bypass a connection error.

Rules that prevent preview errors

• Keep the column order. TrekMail reads the positions shown above. The headers are optional, but if you include them, use the order in these examples.
• Use three columns or six columns. Do not mix the formats in one file.
• File limit: 2 MB and no more than 1,000 data rows. The batch limit is lower on Starter and Pro, and the preview shows the rows allowed for your account.
• Use UTF-8 when exporting from a spreadsheet. TrekMail can handle some legacy encodings, but UTF-8 is the reliable choice for names and passwords with non-English characters.
• Comma, tab, and semicolon separators work. TrekMail detects the separator from the file.
• Blank lines and lines beginning with # are ignored.
• Quote fields that contain a separator. For example, write a comma in a password as "pass,word". A literal quote inside a quoted field is written twice: "pass""word".
• Check each source and destination only appears once. A source mailbox cannot be mapped to more than one destination in the same batch, and a destination cannot accept two source mailboxes in the same batch.
• For six-column files, keep the number of distinct source hosts practical. The preview accepts up to 50 unique hosts at once. Split a larger mixed-provider project into separate batches.

Before you select Start

Preview the file and fix all invalid rows. Common reasons are a missing destination mailbox, an empty source password, a malformed source address, an unsafe or invalid source host, or a duplicate mapping in the file.

For Gmail, Outlook, Yahoo, and iCloud, use the relevant app password if the provider requires one. A normal account password is often rejected when two-step verification is enabled.