IMAP and backup files in the cloud

I have 2 licens of eM Client, one for the PC, one for the Surface Pro 2.
I use IMAP, so I have all emails (6 accounts) in both Computers (and on my Smartphone).
Now I want to backup my mails older then 6 month to Keep the IMAP free.
But I only have this backup on my PC, not on the Surface.

How can I use OneDrive (Skydrive) to have this archive also on the Surface?
How do I configure emClient?

And can you tell me, where are my emails? I mean, I have one 1,5GB file “mail_data.dat” and 5 backup files like (this is also my last one).
When I search for keywords I also get results out of the archive, is this the zip file or the 1.5 GB file?

Thanx a lot,

not sure if I understand the issue here, what are you trying to achieve? Do you want to import the backup you have on your computer to the eM Client to your Surface?

Your emails are stored in different files, there’s no single file where all the emails would be stored, however “mail_data.dat” file is one of the most important files for keeping your emails safe.
The zip file contains the whole database including this particular file.


Hi Paul,
thanks for the reply. My questions look like from a dummy user, sorry.

My idea is to work with both computers via imap. So the dat files on both machines (maybe) are a little bit different, because both em Clients work a little bit different on a working day (eg. the last sync with imap). But all in all I have the same mails on both computers (=IMAP).
But what happens with my old mails in the archive?
When I setup a backup on both machines I will lost some mails (the first computer deletes mails, puts them into the archive and the second computer doesn’t get them).
How can I synchronize the archive and where is the archive file?
We have emails, database, dat files and zip files and an archive. What belongs to what?

You write “The zip file contains the whole database”
The help file says: “Check Enable Backup to allow backup in your email client.”
But what is about the Archive?
So I’m confused. What is in the database? Also my archive?
I thought the word Backup stands for Archive, so I can copy the zip files to the Surface to have my old emails with me. But that’s wrong, isn’t it?

Anyway… In short: What is the best way to work with IMAP and an archive and 2 or more computers?


yes there really is a difference between archive and backup, backup stores all your data including settings of your email etc and archive only collects old emails, there’s not really a safe or easy way how to access just the archive and if you use archiving function on two machines the data will get really messy.

In other words, you don’t want to do that, unless you want to make a complete chaos of your emails.

Solution for this would be using archiving on your email service if you have that option (for example Google allows you to archive the data).

I recommend backing up your data on just one machine and if you by any chance lose your data on either machine you can use the backup for both which contains everything.

I hope this answered all the questions,

Thank you.
If I understand it right I have to do 3 steps every time when I leave my office:

  1. Start a backup on my PC
  2. Copy the backup to the Surface
  3. Restore the backup on the Surface

Well, maybe there must be a better way for the future. The “I have ONE Computer” thing is the past, you know.
We have cloud storing, smartphones, tablets, laptops and PCs with three or more operating Systems.

And in my case: When I sit at my client and he said I sent you an email last summer it would be nice to look in the archive of my Surface.

However thank you,


Hi, I don’t think this is the only solution.
You can use the backup automatically so you don’t have to do it everytime just set it up for a frequency you want.

And I don’t understand why would you need to upload the backup to your surface everytime, you can use both clients on both computers as standard, if you use IMAP all your data will be synchronized just not archived.

I hope this is helpful,