Can I just use Autodiscover instead of DeploymentPro (legacy) to set up my Outlook profiles?
This depends on your migration scenario:
Scenario 1: Migration from On-Premises Exchange to Office 365:
Autodiscover will not work, and the use of DeploymentPro (legacy) is recommended.
The reason for this is that when you have On-Premises Exchange, then Exchange information is being stored in the AD object for each user; this includes the Exchange GUID, database store and server information. This means that when you create a new profile on a computer that is joined to the domain, Outlook is going to get that data out of the AD object instead of using Autodiscover. The result of this is that the old connections are being rebuilt into the new profile. That means that one of two things needs to happen:
1) a manual configuration needs to happen. This would require either each end user going through all the settings to set this up themselves (any false or unknown entries will generate a support ticket), or your support team needs to manually set this up for each end user (either by visiting each end user individually, or by remoting into each computer and setting it up for them. Both of these options are time-consuming and causes downtime for the end user).
2) DeploymentPro (legacy) can be used to automate the profile setup, and reattach any local PST files found on the local drive, and import the signature into the profile.
Scenario 2: Migration from Hosted Exchange to Office 365:
In this case, Autodiscover will work, and you don't necessarily need to use DeploymentPro (legacy), although it does save some time and has some benefits, as outlined below.
The reason that Autodiscover will work in this case is because there is no Exchange information being stored in the AD object for each user. In this case, Autodiscover can be set to automate the setup of your end users' Outlook profiles. If you are using Autodiscover rather than DeploymentPro (legacy) in this scenariom, once Autodiscover has been set and the MX record cutover has been made, inform users to create a new profile. At that time they will be prompted to enter their name, email address, and password so that Autodiscover can then build their profile.
Benefits to using DeploymentPro (legacy), in this scenario: