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Signature 365
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Signature 365
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  • Get started
    • Signing up for a Signature 365 account
    • Creating a new Signature 365 subscription
    • How to setup Signature 365
    • Signature 365 system requirements
    • Signature 365 required permissions
    • Applying signatures to users and groups
    • Adding additional teammates to manage Signature 365
    • Using two-factor authentication with a Signature 365 admin account
    • Enabling single sign-on (SSO) for Signature 365 management accounts
    • How to use the Signature 365 migration wizard
    • Migrating to Signature 365 from Email Signature Manager
    • What types of messages are supported
    • Signature 365 SMTP host list and IP whitelist
    • Signature 365 reliability and security
    • Signature 365 product roadmap
    • How to uninstall Signature 365 from your Microsoft 365 tenant
    • User guides
      • Using the Outlook add-in in Outlook Classic
      • Using the Outlook add-in in Outlook on the web and new Outlook
      • Using the Signature 365 Outlook mobile add-in
    • Service information
      • What is the difference between client-side and server-side signatures?
      • Do my emails remain private when using Signature 365?
      • Do you store my Microsoft 365 Global Administrator credentials?
      • Is Signature 365 GDPR and CCPA compliant?
      • Does Signature 365 support DomainKeys Identified Mail (DKIM)?
      • Does Signature 365 support Entra ID Dynamic Groups?
      • What Entra ID data is synced with Signature 365?
      • Signature 365 Entra ID enterprise applications
      • Signature 365 Exchange mailbox support
      • Signature 365 ports and URLs
      • Signature 365 Outlook add-in manifest versions
      • Removing Email Signature Manager following migration to Signature 365
  • Signature 365 Web Portal
    • Signature templates
      • Getting started with the template editor
      • Template editor menu options
      • Using custom fonts in Signature 365
      • Inserting an email address or telephone as a weblink
      • Using folders
      • Template revisions and draft mode
    • Designing templates
      • Using campaigns and disclaimers
    • Signature rules
      • Assigning a signature to an email alias
      • Signatures for additional and shared mailboxes
    • Fields
      • Using fields in Signature 365
      • Using custom fields in Signature 365
    • Managing images
      • What types of images are supported
    • Folder Permissions
      • Using folder permissions in Signature 365
    • Integration
      • Updating users & groups imported to Signature 365 from Microsoft 365
      • How to register an additional Signature 365 tenant
      • Configuring your Signature 365 Tenant to use hotlinked images
      • Using hotlinked vs embedded images in Outlook
      • Enabling vCards on your Signature 365 tenant
      • Microsoft 365
        • How to enable Sent Items update
        • Inspecting users and groups configured to use server-side injection
        • Moving Signature 365 to a new Microsoft 365 tenant
        • Restrict access to Signature 365 server-side signatures using an Office 365 Security group
        • Setting a Custom Attribute in Exchange Online for use in Signature 365
      • On Premise
        • Active Directory Connector release notes
        • Database Connector release notes
        • Exchange Agent release notes
        • How to install the Database Connector
        • How to install the Exchange Agent
        • Installing the Signature 365 AD Connector
        • Using the Signature 365 Database Connector
    • Troubleshooting
      • Import Active Directory attributes into Signature 365
      • How to update the Sender Policy Framework (SPF) record
      • Managing multiple tenants from the Signature 365 portal
      • Role-based access control in Signature 365
      • Signature 365 domain shows as "Incomplete setup" within Microsoft 365 Admin center
      • Multi-factor recovery process
      • Outlook add-in reports "The request has failed...."
  • Client-side signatures
    • Deployment and configuration
      • How Outlook client-side signatures work
      • How to install the Outlook add-in
      • How to install the Outlook (Classic) agent
      • Updating the Signature 365 Outlook add-in
      • Enable legacy Exchange Online tokens
      • How to enable debug log in Outlook add-in
      • Managing Outlook's default signature options with the Signature 365 Outlook add-in
      • Managing personal signatures, fonts and stationery for "New" Outlook and Outlook on the web
      • Managing personal signatures, fonts and stationery for Outlook Classic desktop
      • How to set Outlook default fonts for all users
      • Version requirements for the Outlook mobile add-in
    • Troubleshooting
      • Current versions of Signature 365 software
      • Supported Outlook versions for Signature 365 client signatures
      • Nested app authentication (NAA) and deprecation of Exchange legacy tokens
      • Outlook add-in is not being deployed to users as expected
      • Outlook add-in is not adding default signatures to email
      • How to enable remote logging in the Outlook add-in
      • Outlook add-in: Opening the Outlook devtools debug window
      • Creating a security group using dynamic group membership
      • Disabling Outlook signatures in New Outlook and OWA
      • Existing outlook email templates insert signature above email body
      • HTML tags are shown for weblinks and images
      • 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
      • 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
      • How Microsoft 365 server-side signatures work
      • Using Server-side injection to specify the location of an inserted signature
      • Inserting a signature in a specific location with Server-side injection
      • Create an exclusion group to exclude users from server-side injection
      • How to update the group assigned for server-side injection
      • Exclude autoreplies from signature insertion
      • Exclude signatures on Microsoft Planner comment emails
      • Tasks, contacts and voting buttons are removed from internal emails sent using Signature 365 server-side signatures
      • Using Signature 365 with read only access to Microsoft 365
      • How to use Signature 365 together with third-party security solutions
      • How to trial Signature 365 when already using another signature service
      • Using Outlook message recall with Signature 365
      • Recreating the Signature 365 Exchange connectors
    • Troubleshooting
      • Enabling server-side injection in Signature 365
      • A signature is not applied to emails with large attachments
      • Unable to contact the Signature 365 service when using the Add-in with an on-premise mailbox
      • Non-delivery report errors and solutions
      • 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
      • Server-side injection - Digital Guardian Agent X-dg headers cause 552 5.3.4 error
      • Signature 365 transport agent debug log file
      • Removing the Signature 365 Mailflow rule and Exchange Connectors
  • Frequently asked questions
    • Outlook (Classic) agent release notes
    • Using Signature 365 in a hybrid configuration with on-premise Exchange mailboxes
    • Using Sent Items update does not work when sending on behalf of another user
    • Apple Mail application replaces images with when replying
    • Using a group policy object to disable signatures in Microsoft Outlook
    • How to capture a HAR log from Microsoft Edge DevTools

Client-side signatures

Documentation for all versions of the Outlook add-in and agent

Deployment and configuration

Guides for deploying Signature 365 client-side signatures, configuring Outlook behavior, and managing related installation requirements.

Troubleshooting

Troubleshooting articles for Signature 365 client-side signatures, Outlook add-ins, mobile support, and common deployment issues.

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