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# Prerequisites: NET Framework 4.5 and Windows Management Framework 4.0
# http://technet.microsoft.com/en-us/library/jj984289.aspx

# Run these commands in the following order

# This will prompt you for your Exchange Online user name and password
$UserCredential = Get-Credential

$Session = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri https://outlook.office365.com/powershell-liveid/ -Credential $UserCredential -Authentication Basic -AllowRedirection

# Corrects the "execution of scripts" error
Set-Executionpolicy -ExecutionPolicy Unrestricted

Import-PSSession $Session

# Create the CSV file
Get-mailbox -ResultSize unlimited | Select-Object Alias, Displayname, UserPrincipalName, EmailAddresses, ExchangeGUID, LegacyExchangeDN | export-csv mailbox.txt -NoTypeInformation

# Run this last when you are ready to exit.
Remove-PSSession $Session
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