At the moment I’m using local folders with different computers (with another mail client). The local folders are safed at a network drive and all installations using the same. With client side caching I can use this folders also without LAN connection.
In the offline folders I have stored 30000 mails. It isn’t possible for me to sync all that mails with IMAP.
Is there a posibility to do the same with EMClient?
Many thanks in advance for your ideas!
Regards
Edi
I don’t see why you can’t sync that many messages with IMAP as it has no practical limit. There are also threads on this forum where users have had substantially more messages than that and I have tested the application with 50k messages with no problem
The only issue I see is size. It may take a while for the first sync.
You can’t use caching with eM Client. It needs the complete database folder and only one computer can access that at a time. Real-time caching like you get with online backup services like Carbonite simply give you an empty database on the server. Unless the backup is set to run when eM Client is closed, then it may work. You did not say what you are using for caching though, so Carbonite is the example I can attest to.
Thanks for your reply! I haven’t so much space at the IMAP server. My offline folders have more than 3 GB. Another point is, I don’t want to safe my data in the cloud. All my backup files are offline.
My offline email folders are like an archive. At the moment, with TheBat!, I can use the folders with my notebook and also with my pc at the office.
Well that is what IMAP was designed for.
You can do it manually, but it is tedious, and unreliable. When you are finished using eM Client on computer 1, do a Menu > File > Backup and copy the zip file to a USB. When you get to computer 2, copy the zip file from the USB and do a Menu > File > Restore . etc. etc. etc. But because of human error, this is not reliable. Also, because the restore completely overwrites the database, if there is new data on computer 2 before you do the restore, it will be lost. On more than two computers, you need to remember what is the latest one you used. It is not a feasible solution.
Maybe if your email provider does not allow 3GB it is time to look for a new one. 
Some examples of mailbox limits with free email services:
AOL - Unlimited
Gmail - 15GB
GMX - up to 10GB + personal storage
iCoud - 5GB to 200GB
Mail.com - Unlimited
Mail.ru - Unlimited
Outlook.com - 15GB
Rediffmail - Unlimited
Yahoo! - 1TB
Zoho - 5-15GB
You are right - backup and restore with different computer is a bad solution. TB! has file based accounts. So it is easy to sync the files. With a database this is not the best idea.
Because of my little business and the law in Germany Gmail isn’t a solution. Gmail I’m only using for Android Playstore. For contacts and calendar I’m using Owncloud.
For my own domain I can use for email 2GB/Account (address). For this a have a hosting account.
For private things like shopping I use a very old Web.de account with 1GB. I hate Web.de, but I have the email address since a very long time. It would be a very long list of accounts I had to change my email address.
BTW: The backup function inside EMClient safes only local dataor is it possible to backup also the mails inside the IMAP account?
Yes, Thunderbird can use mbox format, which is just amazing. It is really just a text file. And with a separate mbox file for each folder it is so easy to selectively backup or sync content. The issue is still there with real-time syncing, but otherwise extremely useful format.
The backup function in eM Client will do the complete database, and that includes IMAP folders. The caveat is your IMAP settings. By default the IMAP messages are headers only, and the content is downloaded only when you click on the message. So in that case your backup will be just headers. If the server data is lost and you do a restore from eM Client, it will not work. To ensure you have the complete message body and attachments, you need to enable offline use.
That will download the full message on arrival, so the backup will include that. It also has the added advantage that your messages should display quicker because there is no or little need to download content when you click on it. Linked content will always need to download regardless of settings. One of the disadvantages of dynamic content, I suppose.
I am trying to recall an SQL sync tool, but not sure of anything that either does not cost a fair bit, or something that is easy enough to use.
If you have a Pro License, open a support ticket with eM Client; they may have some suggestion or solution.
Thanks for your help!
For clarification: I’m testing EMClient after a long time using TheBat and a little bit using Thunderbird. I think EMClient is doing a lot of things much better than the both TB’s. I plan to buy 3 pro licences.
I wonder if it could be possible to use the archiving function? In the manual is not so much information about it. I have read, that the messages stored in local folders. But no information about how I can use the archived messages and what happens with this messages. Are they stored in the database, or realy inside an local folder? Are they sorted in the archive like in the original account? Perhaps the archive can also be a solution for me?!
Automatic Archiving is essentially designed to remove older messages from the server on a specified schedule and store them in Local Folders. They maintain their directory structure, and the archive will appear as a separate folder tree in the left side-bar.
This is still part of the database, but like each account it uses a separate folder within the files stored on your hard disk.
Many thanks! …a lot of information! 
If the archive is a part of the database is synchronizing of this folder perhaps not the best idea. But I can use the offline folders for my old offline mails. I can import all the mails to the 3 computers.
The automatic archiving I can’t use. It could be a solution to use IMAP folders for sorting and, for example, once a year I copy to the offline folders. It’s just a bad work arround, but it’s just the beginning.
Manually syncing of individual SQL database folders and files is tricky. Take for example a single file in the database; mail_data.dat. When eM Client is permanently closed, means it is never changing the file on multiple computers, sync away with no problem.
Now the problem comes when the application is running. mail_data.dat is still there, but it is practically empty as all current activity is now in mail_data.dat-wal. This is the process SQL uses to write data to a write-ahead-log, rather than to the original file. Close eM Client and the data is written back to mail_data.dat and the .wal file is deleted. If the application crashes, the .wal file is used to reconstruct the .dat file.
If you use a cloud backup solution like Carbonite, it will sync the empty .dat file to the cloud, and not the .wal one which is in use. The result - an empty database if restored from the cloud.
And the BIG problem comes where the file has changed on more than one computer. You won’t know which is more recent, or maybe they both are, and different. The result is data loss.
Come a complete circle again because that is exactly what IMAP is for. It is an automatic sync of server data between multiple clients.
Yes, you are right. This is no solution. For the moment I will use IMAP folders and keep only the old “archive” offline. Later I can look for a better solution - more space at the IMAP server. Than I can move the mails online again.