Sync problems

Good afternoon I get in touch with you because of problems with my laptop.
I had to reinstall and set up the application again on the laptop, with the same accounts. What happens to me since the new installation is, that previously when I read the emails on my iphone, these were marked as "Reading " in the application of the laptop, so that they were synchronized. 
Now, when I read an email on the iphone, and open the app on the laptop, I have to mark it as well "read ". 
I would appreciate if you can tell me if there is any specific configuration to be done in the app. Thanks a lot. I’m waiting for your answer. 
Best regards

you can go into menu / settings / mail and check the box that says message read when opened in new windows or if displayed after 10 sec.

It could be because your account in eM Client is setup as POP3, which only downloads new mail from the server, but does not sync the message status with the server.

You can check how your account is setup by going to Menu > Tools > Accounts. You will either have tabs for POP3/SMTP or IMAP/SMTP.

That doesn’t have anything to do with syncing the message status from the server.

Could you verify that the account is set up as IMAP?  If it is set up as POP3, it will not sync, but will just download messages as they come to the inbox.  Go to menu/tools/accounts, select the account and see if there is an “IMAP” or “POP3” tab.

If you set it up as POP3, you will have to set it up again as IMAP and delete the POP3 version.

But be careful about just deleting the POP3 account, because it will delete all the messages in eM Client. You want to move the messages to Local Folders before removing the POP3 account.