- You correspond with two different people who have the same name (for example, John Smith) but different e-mail addresses. In this case, you can split the contact by removing one of the e-mail addresses from it. To do so, open the contact for editing, select the e-mail address that will need to be separated, and click on "Remove". This will cause a new contact with that e-mail address to be created, and all messages with that e-mail address to be relinked to the new contact.
If you erroneously merge several contacts, you can undo the merge by using the "Extract Merged Contacts" feature (it can be accessed through an item in the contact context menu). Extracting the contacts will restore their exact state at the moment of the merge operation, and messages received after the merge will be automatically relinked to one of the extracted contacts based on the names and e-mail addresses used in the messages.
to be continued