Out-of-Office replies and calendar invites route through email servers owned by Microsoft (Office 365) or Google (Gmail/Workspace), rather than your corporate email server where Opensense is configured. This routing behavior impacts how Opensense can handle these message types.
Calendar Invites
Opensense does not stamp calendar invites by default due to inconsistent behavior and functionality issues.
Why calendar invites aren't stamped:
Calendar invites are system-type messages, not standard emails, and shouldn't be treated as such. When Opensense processes these messages, several issues occur:
Loss of functionality – When Opensense touches a calendar invite, it converts the message into a standard email, causing it to lose its calendar invite functionality.
Inconsistent signature application – Stamping can produce unexpected results. For example, if a signature user sends an invite to a non-signature user who then forwards it, Opensense may apply a signature using a mixture of data from both users.
Poor calendar display – The plain text block of the signature can appear in the actual calendar tile, cluttering the calendar view and creating a poor user experience.
Note: This limitation applies to both Microsoft 365 and Google Workspace environments.
Out-of-Office Replies
OOO stamping behavior differs between Microsoft 365 and Google Workspace.
Microsoft 365
OOO stamping is available but requires specific configuration.
Requirements for OOO stamping:
Your domain must meet all three email authentication requirements:
SPF
DKIM
DMARC
When these security protocols are properly configured, OOO replies will route through your email address and server, allowing Opensense to append signatures.
Implementation:
OOO stamping also requires a duplicated mail flow rule to specify how OOO messages are handled. This configuration must be completed by an Opensense Implementation Engineer.
Workaround:
If your authentication requirements aren't met and messages don't route through Opensense for stamping, users will need to use a text-based signature when setting their OOO message.
Why text-based signatures are necessary:
Images cannot be uploaded to OOO messages – they either don't save or break immediately after
Copying and pasting the fully rendered HTML signature also fails – images break immediately upon saving
Google Workspace
Google allows plain text signature blocks in OOO messages.
Users can input the plain text version of their signature directly into the body of the OOO message, and it will route normally without additional configuration. This provides a simple workaround that maintains brand consistency while users are out of the office.
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Opensense Support
For further assistance, contact Opensense Support:
Email: help@opensense.com
Knowledge Base: help.opensense.com