Old email archives often sit around long after someone has moved to a different mail app. It might be a PST from Outlook, an MBOX export, or a folder of EML files copied from an older computer. Synology email backup tool called Mail Backup X can bring those saved messages into a searchable archive on a Synology NAS.

The important distinction is that these files contain previously saved mail; they are not a connection to the original mailbox. Once imported, they give you a way to search through old correspondence even when the account or mail program is no longer in regular use.

Start by locating the archive you want to preserve. It could be sitting in a downloads folder, on an external drive, or somewhere among files copied from an older machine. If there are several archives, check their names and dates before importing anything. Knowing which account or period each file represents will make the archive much easier to organize later.

Keep the original file untouched. Instead, make a working copy and use that for the import. It is a small precaution, but it gives you something to fall back on if the file turns out to be incomplete, mislabeled, or simply not the archive you intended to use.

Rename the working copy so that it identifies the source and, where possible, the period covered by the messages.

Mail Backup X Synology runs on the NAS before you can import an archive.

The setup uses Docker or Container Manager, with a NAS folder mounted at `/data` and port 18080 mapped so the application can be opened through a browser on the local network.

If the application is already running, you can go directly to the sign-in page. Otherwise, complete the container setup first and make sure the NAS folder is mapped correctly.

Also check the available NAS storage before starting, both for the imported archive and for the separate copy you are keeping as a precaution.

Import the archive and check the messages

Inside Mail Backup X, locate the import option and select your working copy. Follow the on-screen prompts for your specific file type. When asked to name the import, be specific. Use the actual source or account name instead of a generic title like “Old Mail.”

Once the import finishes, open the archive and verify the contents. Don’t just assume it worked; open a few recognizable messages to catch any incomplete exports or wrong files before adding more archives to the pile.

• Check the timeline: Open one of the oldest messages and one of the newest. If you expect emails from 2018 to 2022, verify that both ends of that timeframe are present.
• Review the details: Check the sender, date, subject, and body text to ensure everything displays correctly.
• Test attachments: Open a message with an attachment to confirm those files carried over safely.

If a date range seems cut off, check your original source file to see if the initial export was incomplete.

Next, test the search function. Try looking up a familiar sender, company, or specific phrase from a message body. (Mail Backup X supports advanced search operators; check the product’s help documentation for syntax if needed). If a search comes up empty, manually browse the folder to confirm the messages are actually there before you keep tweaking your search query.

If you have multiple archive files, process and verify them one at a time. Keep brief notes on where each file came from and the date ranges you’ve confirmed. Since two exports from the same mailbox can look nearly identical, compare unique messages from each period before deciding a file is a duplicate. Always keep your original files until you are 100% sure everything you need is safely inside Mail Backup X.

Finally, remember that imported files and live account profiles serve completely different purposes. Importing an old PST or MBOX file won’t connect Mail Backup X to your current Gmail or IMAP account. If you want to back up a live account, set up a separate profile with a distinct name. Keeping them clearly separated makes your archive much easier to navigate later on.

Keep the archive or move mail elsewhere

Now that your old messages are safely archived and searchable, you need to decide whether they should simply live on the NAS, or if some need to be moved into a new email program. Mail Backup X allows you to export archived emails back into PST, MBOX, and EML formats.

Choose the format your new email app supports, but start by testing a small batch. For example, you might want your recent client emails in your active inbox while leaving older years on the NAS. Select just one folder or a short date range to export, then open the resulting file in your new mail app. Meticulously check the dates, sender details, text, and attachments. Merely seeing an exported file on your hard drive doesn’t guarantee your new app can read it properly.

If the sample batch opens correctly, go ahead and export the rest of the required messages. Save this output in a separate folder—outside of Mail Backup X’s /data directory—and give it a clear name that includes the mailbox and date range. Hang on to the original archive and the NAS copy until you have fully verified the data in your destination app. Once everything is confirmed, you can decide which copy is the most convenient to keep.

If you are using the free trial, take this opportunity to test an import, browse the messages, and try a small export before purchasing a license. Use a real, appropriately sized archive to ensure the software meets your needs. After all, an old message is only valuable if you can actually find it and confirm it’s intact. By taking the time to use clear names and run a few quick checks, old email archives become far less mysterious. You will always know exactly where the data came from, the dates it covers, and whether your migration worked. Ultimately, Synology email backup tool gives your saved messages a secure, searchable home while you decide exactly what belongs in your daily inbox.