(PowerShell) Hotmail Refresh Access Token (also for Live.com, Outlook.com)

See more OAuth2 Examples

An OAuth2 access token is typically valid for 1 hour. Interaction with the Hotmail account owner via a browser is only needed for getting the initial access token. Once you have it, it can be continually refreshed without user interaction for a long time.

See: How Long can an OAuth2 Access Token be Refreshed?

Chilkat .NET Downloads Chilkat .NET Assemblies

Add-Type -Path "C:\chilkat\ChilkatDotNet47-x64\ChilkatDotNet47.dll"

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

# It is assumed we previously obtained an OAuth2 access token.

# Note: Refreshing an access token does not require user-interaction.  
# Only the act of getting the initial access token requires interactive authorization from the Hotmail account owner 
# (i.e. a browser is displayed and the Hotmail account owner authorizes access by the app).

# Once you have the initial access token, it can be refreshed for a long time.
# A typical strategy is to write your application to automatically refresh the access token 
# when authentication fails, and then retry the operation with the new access token.

$jsonToken = New-Object Chilkat.JsonObject
$success = $jsonToken.LoadFile("qa_data/tokens/hotmail.json")
if ($success -ne $true) {
    $("Failed to load office365.json")
    exit
}

# The access token JSON looks like this:

# {
#   "token_type": "Bearer",
#   "scope": "https://outlook.office.com/SMTP.Send https://outlook.office.com/IMAP.AccessAsUser.All https://outlook.office.com/POP.AccessAsUser.All",
#   "expires_in": 3600,
#   "ext_expires_in": 3600,
#   "access_token": "EwBoA+ ... 7pOYcWr5pFwQgI=",
#   "refresh_token": "M.C546_BL2.0.U.-CkW ... g5CKSlDBQ$$",
#   "id_token": "eyJ0e ... 2iiu5iqBK9n7s3A"
# }

$oauth2 = New-Object Chilkat.OAuth2

# See Microsoft OAuth2 Authorization Endpoint
$oauth2.TokenEndpoint = "https://login.microsoftonline.com/common/oauth2/v2.0/token"

# Replace this with your actual App Registration's Application (client) ID.
$oauth2.ClientId = "CLIENT_ID"

# Get the "refresh_token"
$oauth2.RefreshToken = $jsonToken.StringOf("refresh_token")

# Send the HTTP POST to refresh the access token..
$success = $oauth2.RefreshAccessToken()
if ($success -ne $true) {
    $($oauth2.LastErrorText)
    exit
}

$($oauth2.LastErrorText)

$("New access token: " + $oauth2.AccessToken)
$("New refresh token: " + $oauth2.RefreshToken)

# Update the JSON with the new tokens.
$jsonToken.UpdateString("access_token",$oauth2.AccessToken)
$jsonToken.UpdateString("refresh_token",$oauth2.RefreshToken)

# Save the new JSON access token response to a file.
$sbJson = New-Object Chilkat.StringBuilder
$jsonToken.EmitCompact = $false
$jsonToken.EmitSb($sbJson)
$sbJson.WriteFile("qa_data/tokens/hotmail.json","utf-8",$false)

$("OAuth2 authorization granted!")
$("New Access Token = " + $oauth2.AccessToken)