StrataMail Email Continuity
Your team keeps working. Even when your mail server doesn't.
StrataMail Email Continuity captures every inbound message the moment your primary mail server goes down. Mail lands in a shadow mailbox immediately — users log in via branded webmail and keep reading, replying, and sending without interruption. When your server recovers, the relay queue delivers everything automatically. No mail lost. No one locked out.
Just need queue protection, no webmail? → See StrataMail Backup MX Services
What StrataMail Email Continuity Does
StrataMail Email Continuity is a full business continuity service for inbound email. It does two things simultaneously during an outage event:
1. Shadow mailbox — immediate access
Every inbound message is stored locally in a continuity mailbox the moment it arrives. Users do not wait for recovery. They log into branded Roundcube webmail and their mail is already there. They can read, reply, and send exactly as they normally would — from any device, any browser.
2. Relay queue — automatic recovery
At the same time, every message is queued for delivery to the primary mail server. When the primary recovers, the relay queue flushes automatically — every message delivers in order, every 5 minutes until the queue is clear. No manual steps. No lost mail.
This dual-delivery architecture is what separates StrataMail Email Continuity from simple backup MX services, which only queue and redeliver — no webmail access during the outage event. See the full comparison →
What Users Experience During an Outage Event
- StrataMail begins accepting inbound mail immediately — no bounces, no sender errors
- Each message is stored in the user's continuity mailbox in real time
- Users are notified — by IT, or automatically via StrataMail's outage alert system
- Users navigate to the webmail portal — branded with the reseller's or company's identity
- Their mail is already there — everything that arrived during the outage event is waiting
- Users read, reply, and send normally — full webmail functionality, no limitations
- When the primary mail server recovers, StrataMail detects it automatically
- The relay queue flushes — all mail delivers to the primary server
- No manual intervention required at any step
Three Delivery Configurations
StrataMail Email Continuity works in three configurations depending on the customer's existing spam filter setup.
Configuration A — SpamWeeder Premium (Recommended)
SpamWeeder Premium is the primary MX for the domain. It filters all inbound mail. When the primary mail server is unreachable, SpamWeeder's native multi-destination delivery automatically routes to StrataMail — no DNS MX record change needed. SpamWeeder handles the failover trigger natively.
| Step | What Happens |
|---|---|
| 1 | Inbound mail arrives at SpamWeeder (primary MX) |
| 2 | SpamWeeder filters — spam and malware blocked |
| 3 | Clean mail delivered to primary mail server |
| 4 | Primary goes down — SpamWeeder detects failure and activates multi-destination failover |
| 5 | SpamWeeder routes to StrataMail — no DNS change required |
| 6 | StrataMail stores mail in shadow mailbox + queues for relay |
| 7 | Primary recovers — relay queue drains automatically |
Configuration B — Customer-Supplied Filter
The customer's existing filter — Proofpoint, Mimecast, Barracuda, Microsoft Defender, or another enterprise platform — is the primary MX. StrataMail is configured as the alternate delivery destination inside the filter's admin console. The filter's own failover mechanism handles routing to StrataMail when the primary is unreachable.
| Step | What Happens |
|---|---|
| 1 | Inbound mail arrives at customer's filter (primary MX) |
| 2 | Filter processes mail per existing configuration |
| 3 | Clean mail delivered to primary mail server |
| 4 | Primary goes down — filter routes to StrataMail per alternate delivery config |
| 5 | StrataMail stores mail in shadow mailbox + queues for relay |
| 6 | Primary recovers — relay queue drains automatically |
Configuration C — DNS Secondary MX (No Filter)
For customers without a spam filter, StrataMail can be configured as a lower-priority DNS MX record. When the primary MX is unreachable, sending servers fall back to StrataMail automatically. Configuration C provides relay-queue-only protection — no shadow mailbox, no webmail access during the outage event. For full continuity with webmail access, Configuration A or B is required.
The M365 Migration Use Case
Migrating between Microsoft 365 tenants? StrataMail Email Continuity is the safety net under your cutover. During a tenant-to-tenant migration, DNS propagation can take hours or days. Mail arrives unpredictably at either tenant during the propagation window — and standard migration tools like BitTitan and Quest handle mailbox data, not inbound mail safety.
| The Problem | The StrataMail Solution |
|---|---|
| DNS propagation takes hours — sometimes days | StrataMail acts as a neutral catch-all during the window |
| Mail arrives at the wrong tenant, gets bounced or lost | All mail captured by StrataMail regardless of DNS state |
| Migration tools don't protect inbound mail | StrataMail fills the gap — safety net under the migration |
| Users lose email access during cutover | Shadow mailbox gives users webmail access throughout |
| IT has no visibility into what arrived | Admin panel shows queue depth, delivery status, event log |
Learn about M365 Migration Coverage →
DKIM Preservation
StrataMail Email Continuity preserves DKIM signatures on all relayed messages. When mail is queued during an outage event and redelivered to the primary server after recovery, the original DKIM signature is intact. This matters for organizations using M365 Distribution Groups or other platforms that require valid DKIM for internal mail processing. Messages relayed through StrataMail arrive at the primary server with their original DKIM headers — no signature stripping, no validation failures.
Supported Primary Mail Platforms
StrataMail Email Continuity works with any SMTP-reachable primary mail server, including: Microsoft 365 (Exchange Online), Google Workspace (Gmail), Microsoft Exchange (on-premises), cPanel / WHM, Plesk, Zimbra, Postfix, Sendmail, Exim, Kerio Connect, and any SMTP-compatible mail platform.
Reseller & MSP Program
StrataMail Email Continuity is built as a reseller platform. Add full business continuity to every customer domain — under your own brand, with your own pricing, from a single reseller account.
- White-labeled admin control panel — your logo, your colors, your brand
- White-labeled Roundcube webmail — your branding on the portal customers use during outage events
- Per-domain provisioning — add and manage customer domains through the portal
- Usage dashboard — domain status, queue depth, outage events, relay activity
- Outage alerts — email and SMS notifications when a customer's primary goes down
- Branded alert emails — alerts sent from your address, not ours
- Volume pricing — effective rates from $3.00–$6.00/domain/month depending on tier
- Dedicated reseller support channel
Reseller tiers start at $29.99/month for up to 5 domains.
View Reseller Pricing → | Learn About the Reseller Program →
Direct Customer Pricing
- $18.00/domain/month — includes shadow mailbox, relay queue, 30-day retention, monitoring, and outage alerts
- One-time setup fee: $149/domain
- SpamWeeder Premium add-on: +$9.00/domain/month
Protecting 5 or more domains? The reseller Starter tier at $29.99/month is a better value. See the comparison →
