To begin, log in to Exchange ECP as an administrator and navigate to servers->database. From there, you will need to create a new mailbox database. Click on the + sign to create a new database, then fill out the necessary information and click save.
Once the database has been created, click on compliance management –> retention tags.
Click plus to create a new tag. In the tag shown below, we are going to move e-mails to the archive database after a period of 2 years (730 days).
Next, navigate to compliance management –> retention policies. Create a new retention policy and add the retention tag we previously created to the policy. You can add multiple retention tags if for example, you want the archive e-mails deleted after 5 years. In our example, we are only using the single retention tag we created, so e-mails will be archived after 2 years and then kept indefinitely.
Adding Users to the Retention Policy
To add users to the policy, navigate to recipients-> mailboxes and edit user. From the mailbox features, select the retention policy that you want for the user.
Select enable from the mailbox features to enable archiving for the user.
Next, select the archive database that will be used to store the archived e-mail.
When finished, click on the save button. Wait up to 24 hours for the Exchange housekeeping to neatly archive the user’s mail in to the new Archive database. You can access the archived e-mail via Outlook Web Access.