After having to reinstall eM Client on a new laptop I lost all my saved emails and contacts., can I retrieve them from an online server?

After having to reinstall eM Client on a new laptop I have lost all my saved emails and contacts. Is there a way to retrieve them from an online server?

was your email setup as an IMAP server.  if it was you should be OK if it was a POP server you will have to back them up on the old PC.  If you old PC crashed they are lost

The new one is IMAP server, but to be honest, I believe it may have been POP on the old one, I’m not 100% sure.  Thank you.

if it was POP?  and depending on the email program you were using.  you maybe able to recover you emails.  can you still access your old pc?   if it won’t boot take it to someone that can plug your old hard drive into another PC and see if you can read it.   Outlook will leave a PST file and other programs will leave a database type if file that hold you emails and contacts.  you may be able to convert them to .eml for em client and than import them