📬Mail Server Settings

Various information about configuring Squirrel for well known mail providers

Gmail / Google Mail: POP3 / IMAP

1. Enable POP3 and/or IMAP in your Gmail settings:
 For POP3 see https://support.google.com/mail/answer/7104828
 For IMAP see https://support.google.com/googlecloud/answer/10636934

2. Create an Google App Password for Squirrel: See https://support.google.com/accounts/answer/185833

3. Use the App Password instead of the normal Gmail user password in your Squirrel subscription document

Protocol	Mail Server	Port
POP3S	pop.gmail.com	995
IMAPS	imap.gmail.com	993

Microsoft 365 Outlook Mail: POP3 / IMAP with OAuth 2.0

The support for OAuth 2.0 Client Credentials grant type with IMAP and POP3 access on the Azure platform is available as of July 1st, 2022. Please follow the steps carefully in setting up the application id and the client credentials:

• Microsoft identity platform and the OAuth 2.0 client credentials flow

• Authenticate an IMAP, POP or SMTP connection using OAuth

Important Notes

• Add the Application Type API permission Office 365 Exchange Online > IMAP.AccessAsApp or POP.AccessAsApp depending on the protocol to be used.

• These API permissions do require admin consent.

• Do not forget to issue the required PowerShell commands (see below).

• Use the hostname outlook.office365.com in the connection document.

Microsoft Entra

PowerShell Command Example

Install-Module -Name ExchangeOnlineManagement
Import-module ExchangeOnlineManagement
Connect-ExchangeOnline -Organization {Azure-Tenant-ID}
New-ServicePrincipal -AppId {Enterprise-Application-ID} -ServiceId {Enterprise-Object-ID}
Add-MailboxPermission -Identity "{Email-Address}" -User {Enterprise-Application-ID} -AccessRights FullAccess

The client secret generatzed by Microsoft 365 will expire after the specified period and will have to be renewed.

Field Assignments

Subscription Document	Example value
Authorization Token Endpoint	https://login.microsoftonline.com/11111111-2222-3333-4444-55555555555/oauth2/v2.0/token
Authorization Scope	https://outlook.office365.com/.default
Client/Application ID	66666666-7777-888-9999-11111111111
Client Value/Secret	puG8Qak340dhfnskfrieuhnfe3dr.456saa.O