Enable Mailbox’s UM features with Lync On-Premises

I have a call today from a customer that has Lync on-premises already deployed. He moved from Exchange on-premises to Exchange Online a while ago and had the UM integration between Lync and Exchange Online already configured. He finally moved his users from a E1 plan to E3 plan and wanted to know how to enable VM and other UM features. I wrote the following instructions for him that I want to share with all of you:

I.                   Enable UM in the mailbox:

1.       On Exchange Online: Manage My Organization/User & Groups/Mailboxes, open the user's mailbox

2.       Expand Phone & Voice Features

3.       Click on Unified Messaging and then click on Enable

4.       On Enable UM Mailbox (Step 1 of 2), click Browse and select a UM Dial Plan Policy

5.       On Enable UM Mailbox (Step 2 of 2), leave the default values (or change the extension if necessary)

6.       Click Ok to save

II.                 Assign a Hosted UM Policy to the users:

1.       Connect to the Lync pool using Power Shell:
$cred = get-credential
$session = New-PSSession -ConnectionUri https://lyncpool.domain.com/ocspowershell -Credential $cred
Import-PSSession $session

2.       Run the following PowerShell commands:
Grant-csHostedVoiceMailPolicy -identity <user> -PolicyName "Exchange Online"
Set-csUser -identity <user> - HostedVoicemail $true

Very straight forward steps. I hope this post is helpful to you.