I had a to by another harddisk. I had a pro-license. What do i do to restore it?

I had a to by another harddisk. I had a pro-license. What do i do to restore it? All my data is gone, but I have a backupof mail-data.dat. How can i restore it?

You can go to the license manager site https://licensemanager.emclient.com/account/login?returnUrl= and deactivate the license from your old drive.  If you can still access the old drive, you can go to menu/help/license and select deactivate.  The login information was provided to you at the time you purchased the pro license.  If you don’t have this, you can go here to reset credentials http://www.emclient.com/reset-password

After you install the new instance of eM Client on your new drive, go to menu/help/license and enter your Pro license key.  If yo don’t have the license key, you can request it from eM Client by going to https://www.emclient.com/lost-activation-key.  They will send it to you via email.

Then, go to menu/file/restore to restore from the backup.