Requirements and planning
Prepare Windows, Microsoft 365, network, sender, and device prerequisites.
Read documentationAdministrator documentation
Operate RelayBridge
with the boundaries visible.
Product procedures for RelayBridge v1.0.0-rc.1—from the supported Windows installer through Microsoft 365 setup, device intake, durable delivery, diagnostics, and servicing.
Current release v1.0.0-rc.1 · Preview · Unsigned public release candidate for evaluation and community testing. A signed stable release is not yet available. Review release status.
First-time path
From installer
to a verified test.
RelayBridge runs locally on Windows, accepts deliberately restricted SMTP from a trusted private LAN, and delivers to Exchange Online using certificate-based application identity, STARTTLS, and XOAUTH2.
- 01Install RelayBridgeOpen procedure
- 02Set up Microsoft 365Open procedure
- 03Prepare printer connectivityOpen procedure
- 04Add and configure a deviceOpen procedure
- 05Test local and upstream deliveryOpen procedure
- 06Operate and troubleshootOpen procedure
Know the RC1 boundaries before testing
Inbound device SMTP has no STARTTLS, Windows Firewall configuration is manual, management is loopback-only, release checking is manual, delivery is at-least-once, and this build is unsigned. Read the complete RC1 limitations before connecting devices.
Getting started
Prepare the host and complete the supported RC1 installation and first-run sequence.
Install RelayBridge RC1
Use the supported bootstrapper and complete the local installation.
Read documentationFirst-run checklist
Move from installation through Microsoft setup, device configuration, and testing.
Read documentationMicrosoft 365
Provision a customer-owned identity and sender-scoped Exchange authorization through the released wizard.
Microsoft 365 setup
Complete the released wizard and activate a verified candidate.
Read documentationIdentity and certificate
Understand the customer-owned Entra application and local certificate.
Read documentationExchange RBAC
Scope SMTP authorization to one selected sender mailbox.
Read documentationStep 5 verification
Handle bounded verification and possible Exchange propagation safely.
Read documentationDevices
Expose one narrow private listener and authorize each printer, appliance, or legacy application.
Printer connectivity
Bind the private listener, apply the configuration, and handle Windows Firewall.
Read documentationAdd a device
Create a printer or legacy SMTP device and send a synthetic test.
Read documentationSecurity modes
Choose Authenticated or Legacy mode and enforce source and sender restrictions.
Read documentationOperations
Interpret queue state, collect evidence, and service the installed Windows application.
Queue and delivery
Interpret durable local acceptance, retries, and Exchange Online acceptance.
Read documentationDiagnostics and support
Collect bounded health evidence and review sanitized support bundles.
Read documentationServicing
Restart, upgrade, repair, or uninstall without losing track of retained state.
Read documentationSecurity
Understand implemented controls, administrator responsibilities, residual risks, and current limitations.
Security model
Review implemented controls, administrator responsibilities, residual risks, and RC1 limitations.
Read documentationTroubleshooting
Start from the symptom and preserve the security boundaries while collecting evidence.
Troubleshooting RelayBridge
Follow symptom-led checks without weakening the product boundaries.
Read documentationReference
Use verified Windows paths, ports, versions, release links, and reporting channels.
Administrator reference
Find verified paths, endpoints, versions, licenses, and support links.
Read documentationDeeper background
Product procedures here.
Problem-solving guides there.
The documentation describes the released RelayBridge workflow. The guides explain broader Microsoft 365 SMTP choices, migrations, device limitations, TLS failures, and Exchange responses without duplicating the product procedures.