Blog
Migration write-ups, pitfalls and providers.
We write about what actually breaks when mail moves: new provider limits, authentication, deliverability after the move, running your own mail server.
App passwords: why you need one and where to get it
A separate password for IMAP instead of your account one: who requires it, where each provider keeps it, and what to do when the section will not appear.
ReadHow long does moving a mailbox take
Speed is capped by the two mail servers, not by the software. How to estimate the time in advance and what to expect from a mailbox of tens of gigabytes.
ReadWhy a Gmail migration doubles your message count
Labels versus folders and the All Mail folder: the number one cause of doubled volume and duplicates, and what to exclude before you start.
ReadMoving mail when you change hosting, step by step
One rule: mail first, DNS second. The full sequence, including TTL, the catch-up pass and the window when messages land in both mailboxes.
ReadMigrating company mail: ten mailboxes and up
What makes a company move different is coordination, not volume. The working order, the inventory, the checks and the note to your colleagues.
Readimapsync without the command line
The same imapsync, minus Perl, dependencies and Windows build roulette. What it does, what it does not, and the full command it runs.
ReadWhat to do when a migration is interrupted
Restarting is a normal part of the process, not disaster recovery. Why a repeat run is cheap, duplicate-free, and what to check before it.
ReadIMAP versus POP3: why migrations only use IMAP
POP3 has no folders, keeps no message state and deletes from the server by default. What that means for a move, and the workaround when IMAP is off.
ReadHow to check that everything made it across
Compare messages per folder, not volume: the gigabytes never match and that is fine. The checking order and the signs that something is missing.
ReadFolder separators: Dovecot / versus Courier .
Why Clients/2025 turns into a folder with a dot in its name, where flat lists come from, and what automatic mapping does about it.
ReadOAuth 2.0 for Microsoft 365: when app passwords do not exist
Basic auth is off in Exchange Online and app passwords are not offered. What replaces them, which permission is needed, and what to do without admin rights.
ReadMail lands in spam after the move: SPF, DKIM and DMARC
A migration copies incoming mail; what lands in spam is outgoing. The three DNS records to set and the order to verify them in.
ReadFind out how big your mailbox is. It costs nothing.
Connect two servers, look at the size and decide. Or take the client and keep everything on your side.
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