Customer PlaybooksOutlook Add-in — Customer Playbook

Outlook Signature Management — Add-in Customer Playbook

Outlook signature management for AdtoSign customers — deploy, use, and troubleshoot the Outlook add-in

For AdtoSign Customers | How to deploy, use, and troubleshoot the AdtoSign Outlook add-in

What the Outlook Add-in Does

The AdtoSign Outlook add-in automatically applies professional email signatures to every email you compose in Outlook. It also lets you request reviews from recipients with a single click.

Key Capabilities

  • Automatic signature injection: Signature appears when you open a new compose window
  • Works on all Outlook platforms: Desktop (Classic & New), Web (OWA), Mac
  • Review requests: One-click "Request a Review" button in the task pane
  • Campaign banners: Promotional banners automatically included
  • No manual setup per user: Signatures are managed centrally by your admin
  • Image embedding: All images are inline (no "download images" prompt for recipients)

Installation

For IT Administrators

  1. Go to Microsoft 365 Admin Center > Settings > Integrated apps
  2. Click Upload custom apps
  3. Enter the AdtoSign manifest URL (provided by your AdtoSign admin)
  4. Assign to users/groups
  5. Wait up to 24 hours for propagation

Option 2: File Sideload (For testing or small teams)

  1. Download the manifest XML from AdtoSign
  2. In Outlook Desktop: File > Manage Add-ins > Add from File
  3. Select the downloaded XML file
  4. Click Install

Option 3: Direct URL (If enabled by M365 admin)

  1. In Outlook: Home > Get Add-ins
  2. Click Add from URL
  3. Enter the AdtoSign manifest URL
  4. Click Install

Note: If "Add from URL" is greyed out, your M365 admin has disabled custom add-in installation. Contact your IT admin or use file sideload instead.

For End Users

Once your IT admin has deployed the add-in:

  1. Open Outlook
  2. The AdtoSign task pane should appear automatically
  3. If not, look for the AdtoSign button in the ribbon or Home tab
  4. Click to open the task pane

Using the Add-in

Composing an Email

  1. Open a new email in Outlook
  2. Your signature automatically appears in the compose window
  3. If you don't see it, check the AdtoSign task pane for status

Requesting a Review

  1. While composing an email, open the AdtoSign task pane
  2. Click Request a Review
  3. The review call-to-action is inserted into your email
  4. Send the email as normal

Note: The review button only appears if your admin has enabled reviews for your organization. If you see "not enabled", contact your admin.

What Happens at Send Time

  • Images are embedded as inline attachments (CID) — recipients never see "download images" prompts
  • Tracking headers are added (X-AdtoSign-Signed, X-AdtoSign-Compose-Type)
  • Signature is finalized — the add-in ensures the correct signature version is sent

Platform-Specific Behavior

Outlook Desktop (Classic Win32)

  • Signature is placed in the managed signature slot
  • Images are embedded as CID attachments at send
  • Full fidelity — no sanitization

Outlook on the Web (OWA)

  • Signature is written directly to the email body (not the managed slot)
  • This ensures full fidelity (OWA sanitizer would degrade slot-based signatures)
  • Images are handled natively by the browser

New Outlook for Windows

  • Signature is written to the body (like OWA)
  • At send, images are converted to CID attachments (Monarch requires this)
  • Full fidelity with correct image embedding

Outlook for Mac

  • Signature is placed in the managed signature slot
  • At send, images are converted to CID attachments
  • Full fidelity

Troubleshooting

Add-in Not Showing in Outlook

  1. Check with your IT admin — the add-in may not be deployed to you yet
  2. Try restarting Outlook — add-ins can take a moment to load
  3. Check if "Add from URL" is enabled — your M365 tenant may block custom add-ins
  4. Try file sideload — if your admin provides the manifest XML file

Signature Not Appearing in Compose

  1. Check the task pane — does it show your signature?
  2. Verify you're in the directory — your admin must sync you from the organization directory
  3. Check if a signature is assigned — your admin must assign a master signature to you
  4. Wait 5 minutes — the add-in caches the signature for 5 minutes
  5. Restart Outlook — forces a fresh signature fetch

"Attachments Failed to Upload" Error

This happens in New Outlook for Windows when images aren't properly embedded:

  • Ensure your admin has the latest add-in version (manifest >= 3.5.35.0)
  • Contact AdtoSign support if the issue persists

Review Request Button Not Working

  1. Check if reviews are enabled — your admin must enable reviews on your signature
  2. Check if you have recipients — the button needs at least one recipient
  3. Try again — the button may be temporarily disabled after a successful insert

Signature Looks Different on Web vs Desktop

This is expected behavior — OWA's HTML sanitizer processes signatures differently. The add-in handles this automatically by writing to the body on web hosts. If you notice missing icons:

  • Ensure your admin has the latest add-in version (>= 3.4.10.0)
  • Contact AdtoSign support

Best Practices

For IT Admins

  1. Deploy via M365 Admin Center for organization-wide rollout
  2. Test with a small group first before mass deployment
  3. Keep the add-in updated — manifest version bumps include critical fixes
  4. Enable directory sync before deploying the add-in — users need to be synced first
  5. Monitor the deployment page in AdtoSign for add-in status

For End Users

  1. Keep Outlook updated — latest Outlook versions have better add-in support
  2. Don't manually edit your signature in Outlook — AdtoSign manages it automatically
  3. Use the task pane for reviews — don't try to manually add review links
  4. Report issues to your IT admin — include screenshots and Outlook version

References

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