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Signature 365
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Signature 365
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  • Get Started
    • Service Information
      • Do my emails remain private when using Signature 365?
      • Do you store my Microsoft 365 Global Administrator credentials?
      • Does Signature 365 support Azure Active Directory (Azure AD) Dynamic Groups?
      • Does Signature 365 support DomainKeys Identified Mail (DKIM)?
      • Is Signature 365 GDPR and CCPA compliant?
      • Removing Email Signature Manager following migration to Signature 365
      • Signature 365 Entra ID Enterprise applications
      • Signature 365 Exchange Mailbox support
      • Signature 365 Outlook Add-in Manifest versions
      • Signature 365 ports and URLs
      • What Entra ID data is synced with Signature 365?
      • What is the difference between client-side and server-side signatures?
    • Creating a new Signature 365 subscription
    • Enabling Single sign-on (SSO) for Signature 365 management accounts
    • How to setup Signature 365
    • How to uninstall Signature 365 from your Microsoft 365 tenant
    • How to use the Signature 365 migration wizard
    • Migrating to Signature 365 from Email Signature Manager
    • Adding additional Teammates to manage Signature 365
    • Signature 365 development roadmap
    • Signature 365 reliability and security
    • Signature 365 required permissions
    • Signature 365 SMTP host list and IP whitelist
    • Signature 365 system requirements
    • Signing up for a Signature 365 account
    • Upcoming features
    • User Guides
      • Using the Outlook add-in in Outlook Classic
      • Using the Outlook add-in in Outlook Web Access and New Outlook
      • Using the Signature 365 Outlook mobile add-in
    • Applying Signatures to users and groups
    • Using two-factor authentication with a Signature 365 admin account
    • What types of messages are supported
  • Signature 365 Web Portal
    • Designing Templates
      • Using Campaigns and Disclaimers
    • Fields
      • Using custom fields in Signature 365
      • Using Fields in Signature 365
    • Integration
      • Configuring your Signature 365 Tenant to use hotlinked images
      • Enabling Vcards on your Signature 365 tenant
      • Registering an additional Signature 365 tenant
      • Updating users & groups imported to Signature 365 from Microsoft 365
      • Using hotlinked vs embedded images in Outlook
    • Managing Images
      • What types of images are supported
    • Signature Rules
      • Assigning a Signature to an email alias
      • Signatures for additional and shared mailboxes
    • Signature Templates
      • Getting started with the template editor
      • Inserting an email address or telephone as a weblink
      • Template editor menu options
      • Template revisions and draft mode
      • Using custom fonts in Signature 365
      • Using Folders
    • Troubleshooting
      • How to update the Sender Policy Framework (SPF) record
      • Import Active Directory attributes into Signature 365
      • Managing multiple tenants from the Signature 365 portal
      • Multi-factor recovery process
      • Outlook add-in reports "The request has failed...."
      • Role Based Access Control in Signature 365
      • Signature 365 domain shows as "Incomplete setup" within Microsoft 365 Admin center
  • Client-Side Signatures
    • Deployment and configuration
      • Enable legacy Exchange Online tokens
      • How Outlook client-side signatures work
      • How to enable debug log in Outlook add-in
      • How to install the Outlook (Classic) agent
      • How to install the Outlook add-in
      • How to set Outlook default fonts for all users
      • Managing Outlook's default signature options with the Signature 365 Outlook add-in
      • Managing personal signatures, fonts and stationary for Classic Outlook desktop
      • Managing personal signatures, fonts and stationery for "New" Outlook and Outlook Web Access
      • Updating the Signature 365 Outlook add-in
      • Version requirements for the Outlook mobile Add-in
    • Troubleshooting
      • Creating a security group using dynamic group membership
      • Current versions of Signature 365 software
      • Disabling Outlook signatures in New Outlook and OWA
      • Existing outlook email templates insert signature above email body
      • How to enable remote logging in the Outlook Add-in
      • HTML tags are shown for weblinks and images
      • Nested app authentication (NAA) and deprecation of Exchange legacy tokens
      • Outlook add-in is not adding default signatures to email
      • Outlook add-in is not being deployed to users as expected
      • Outlook add-in: Opening the Outlook devtools debug window
      • Outlook Classic inserts a ? instead of the correct character when adding a Signature 365 signature
      • Outlook Desktop - Images appear as attachments when email is saved as draft
      • Signature 365 agent authentication script error
      • Signature 365 Classic Agent cannot support Microsoft One Outlook
      • Signature 365 Outlook Add-in is removed after log out
      • Signature images appear as attachments in web mail services
      • Supported Outlook versions for Signature 365 client signatures
      • Using S/MIME with Outlook Mobile
      • Using the Aptos font in Signature 365
      • Using the Outlook mobile add-in in GCC environments
  • Server-Side Signatures
    • Deployment and configuration
      • Create an exclusion group to exclude users from server-side injection
      • Exclude Autoreplies from Signature insertion
      • Exclude signatures on Microsoft Planner comment emails
      • How Microsoft 365 server-side signatures work
      • How to trial Signature 365 when already using another signature service
      • How to update the group assigned for server-side injection
      • How to use Signature 365 together with third-party security solutions
      • Inserting a signature in a specific location with Server-side injection
      • Recreating the Signature 365 Exchange connectors
      • Tasks, contacts and voting buttons are removed from internal emails sent using Signature 365 server-side signatures
      • Using Outlook message recall with Signature 365
      • Using Server-side injection to specify the location of an inserted signature
      • Using Signature 365 with read only access to Microsoft 365
    • Troubleshooting
      • A signature is not applied to emails with large attachments
      • Enabling server-side injection in Signature 365
      • Non-delivery report 550 5.1.8 Access denied, bad outbound sender
      • Non-delivery report 550 5.4.1 Recipient address rejected: Access denied
      • Non-delivery report 550 5.7.1 Unable to relay this email
      • Non-delivery report 552 5.3.4 Header size exceeds fixed maximum size
      • Non-delivery report errors and solutions
      • Removing the Signature 365 Mailflow rule and Exchange Connectors
      • Server-side injection - Digital Guardian Agent X-dg headers cause 552 5.3.4 error
      • Signature 365 Transport Agent Debug Log File
      • Unable to contact the Signature 365 service when using the Add-in with an on-premise mailbox
  • Frequently Asked Questions
    • Apple Mail application replaces images with when replying
    • How to capture a HAR log from Microsoft Edge DevTools
    • Outlook (Classic) agent release notes
    • Using a group policy object to disable signatures in Microsoft Outlook
    • Using Sent Items Update does not work when sending on behalf of another user
    • Using Signature 365 in a hybrid configuration with on-premise Exchange mailboxes

Server-Side Signatures

Documentation for server-side signature injection

Deployment and configuration

Setup and configuration guides for Signature 365 server-side signatures in Microsoft 365.

Troubleshooting

Troubleshooting articles for Signature 365 server-side signature delivery, routing, and setup issues.

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