Duplicate Email Signature Stamping
A signature appearing twice on the same message, almost always caused by a server-side rule stamping a signature onto an email that already carries one applied by the mail client.
What is Duplicate Email Signature Stamping?
Duplicate signatures are the most common visible failure in server-side signature deployment and the cause is nearly always the same: two systems are applying a signature to the same message and neither knows about the other. The usual combination is a server-side transport rule stamping every outbound message while individual users still have a signature configured in Outlook or Gmail from before the rollout. The message leaves the client with one signature, the server adds another, and the recipient sees both. Three other variants occur. A message in a reply thread gets stamped again on each reply, producing a signature after every quoted section, which is why most platforms offer a first-message-only setting. Two vendors running simultaneously during a migration both stamp. And a rule scoped to the whole tenant catches mail from a connected application or a shared mailbox that already includes a signature in its template. The fix sequence is to clear client-side signatures before or at the moment the server-side rule goes live, scope the rule to exclude application traffic, and configure reply behaviour deliberately rather than leaving it at default.
Also known as
With SyncSignature's server-side signature application, your team gets directory sync and one-click deployment across Google Workspace and Microsoft 365.
How does SyncSignature implement Duplicate Email Signature Stamping?
SyncSignature supports both client-side install and server-side application. Teams switching from another provider should disable the previous rule before enabling the new one to avoid double stamping during the overlap.