I’m caught in a messy Apple Mail / IMAP migration and I’m on the lookout for a dependable solution to get well all messages together with attachments from my Mac and add them to a brand new IMAP server.
Context
I had a number of mailboxes (about 11 accounts) on Supplier A (Hetzner).
On macOS Apple Mail, I configured these accounts by way of IMAP about 48h earlier than migration.
Then the area and mail moved to Supplier B (Keliweb/cPanel). Mailboxes have been recreated with new passwords.
The IMAP hostname stayed the identical: mail..tld, so after DNS change Apple Mail now factors to the brand new server, however my previous Apple Mail accounts are “damaged/offline” because of password mismatch.
Supplier A not has information accessible (previous server/mailboxes are gone).
What I’ve
In Apple Mail, although the previous accounts are offline and preserve asking for password, I can nonetheless see all emails and even very massive attachments when opening messages (offline too).
I additionally discovered a full native Mail retailer at ~/Library/Mail/V10/ with UUID folders per account, many .emlx and a few .partial.emlx, and attachment recordsdata underneath deep paths like: …/Knowledge/…/Attachments/.pdf
Whole native Mail retailer is ~7 GB.
Purpose
Add every little thing into the brand new server.
I created a giant archival mailbox [email protected] on the brand new server (20GB quota) with folders like:
purple//INBOX, SENT, ARCHIVE, and many others.
Issues
Apple Mail copying/importing by way of IMAP is unreliable. Bulk copy usually “prepares”, then stops mid-way, leaving solely a small portion uploaded and no clear errors.
Importing from V10 into Thunderbird loses attachments. If I import .emlx (or listing/subdirectory import), most messages seem with out attachments (e.g. 50/600 have attachments).
Exporting “On My Mac” mailboxes created whereas accounts have been already offline produces tiny exports (KB), so these native “restoration folders” usually are not actual full copies.
AppleScript automation just isn’t accessible: Apple Mail on my macOS doesn’t assist the save command for messages (“Mail can’t perceive the message ‘save’”).
What I attempted
Apple Mail: copy messages into “On My Mac” folders → export mailbox → export is tiny (KB) for large mailboxes.
Thunderbird + ImportExportTools NG: import from V10 directories → construction imports however attachments principally lacking.
Single-message drag from previous cached view to new IMAP generally works, however bulk operations fail or are inconsistent.
Query
On condition that:
the previous server is gone,
Apple Mail nonetheless shows the complete messages with attachments,
attachments exist as recordsdata on disk underneath V10 “Attachments” paths,
What’s the finest recognized technique to reconstruct/ export full MIME messages (together with attachments) from Apple Mail’s native retailer and re-upload them to a brand new IMAP account?
I’m open to:
scripts/instruments (Python, shell, and many others.),
parsing .emlx + linking to attachment retailer,
any recognized utilities that may rebuild .eml/mbox with attachments from Apple Mail V10.
More information I can present
macOS model (inform me what actual information you want),
pattern .emlx headers (redacted),
listing structure underneath V10 for one mailbox,
whether or not .partial.emlx are concerned for lacking attachments.
Thanks quite a bit — any pointers or confirmed workflows could be massively appreciated.
