Adding same email twice to Outlook

[AndreasGu]

We are currently migrating from one email provider to Office 365.

In a way for the staff to keep their old emails this was the suggested approach. Reason for this is that the staff will be able to have both the historic account and the new account in one account so to say.

a) Add existing email account to Outlook Ie. andreas@domain.com - DONE
b) Add the Office365 account to Outlook, same email as above.

When doing b) we get a conflict saying that we can not have two accounts added with the same email address. Is that possible to override somehow? 

[#2]

@AndreasGu You cannot have the same account added twice.   If the account is Exchange or IMAP, export the old mailbox to a pst file to have as a backup then remove it from outlook and add the new account. (If IMAP, you need to change the views on the folders to see the exported mail.) 

After the Office 365 account is set up in outlook, they can import the pst into Outlook (all or only newer messages) or just keep it as an archive pst if the migration does not include migrating the mail from the old server.