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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
  1. Signature 365
  2. Signature 365 Web Portal

Integration

Browse Signature 365 Web Portal guides for Microsoft 365 integration, tenant setup, images, and vCards.

Configuring your Signature 365 Tenant to use hotlinked images

Request tenant-wide hotlinked images in Signature 365 and understand attachment and red-X trade-offs in supported mail clients.

Enabling Vcards on your Signature 365 tenant

Enable tenant-wide vCards in Signature 365 and use generated contact links in hyperlinks or QR codes.

Registering an additional Signature 365 tenant

Follow the illustrated portal steps to register an additional Signature 365 tenant from your existing account.

Updating users & groups imported to Signature 365 from Microsoft 365

Update which Microsoft 365 users and groups Signature 365 imports, including adding, removing, or importing everyone.

Using hotlinked vs embedded images in Outlook

Compare hotlinked and embedded images in Outlook, including benefits, drawbacks, and common rendering issues.

Using Fields in Signature 365

Understand imported and editable Signature 365 fields, data sources, and where users can update values in the portal or add-in.

Configuring your Signature 365 Tenant to use hotlinked images

Request tenant-wide hotlinked images in Signature 365 and understand attachment and red-X trade-offs in supported mail clients.

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