> For the complete documentation index, see [llms.txt](https://help.nightfall.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.nightfall.ai/data-exfiltration-prevention/exfiltration_endpoint/policies/trigger/printer-support.md). # Printer Support Intercepts documents sent to the print queue before they reach a physical or virtual printer. Nightfall evaluates the document at the OS print subsystem level (CUPS on macOS). Domain collections are not used for this trigger. Monitoring scope is configured by printer selection directly on the policy. > **Platform note:** Printer monitoring is supported on **macOS only**. Windows support is not yet available. **Scope options** * All printers connected to the endpoint. * Specific printers by name or type **Common use cases** * Prevent printing of customer records, payroll data, or legal documents on unmanaged or shared printers. * Block printing to fax-to-email or cloud print services running on the endpoint. **Policy recommendations** * Always include virtual printers in scope. * Scope block actions to all printers except approved print server destinations in environments with dedicated secure print rooms. * Deploy alongside Removable Media policies for full physical exfiltration coverage. * Note: Native "Save to PDF" or "Print to PDF" bypasses the print monitoring and blocking capability. However, if the PDF is subsequently exfiltrated, Nightfall does monitor and block this. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://help.nightfall.ai/data-exfiltration-prevention/exfiltration_endpoint/policies/trigger/printer-support.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.