NEWMailSite 11

Keep Outlook.
Lose Exchange.

MailSite 11 is a Windows-based business email server with native Classic Outlook support for email, calendars, and contacts. Keep familiar client workflows, simplify administration, and run messaging on infrastructure you control.

Start a trialReview Outlook compatibility
Classic Outlook Inbox connected to MailSite 11, showing messages and a reading pane

Works With Every Email Client Your Team Uses

App NameProtocol Compatibility
Microsoft Outlook ClassicMAPI over HTTPS for email, calendars and contacts
Thunderbird DesktopIMAP or EWS for email; TbSync with ActiveSync for calendars and contacts
macOS Mail, Calendar and ContactsExchange Web Services (EWS)
iOS Mail, Calendar and ContactsExchange ActiveSync
Android GmailExchange ActiveSync
Web Browser (ExpressPro)HTTPS for email, calendars and contacts

Classic Outlook and Data Sync.

Data Sovereignty

Your mail stays where you decide. MailSite runs on Windows servers you choose: on premises, in your own data center, or with a hosting provider in the region you require.

Deployment guide
Choose the locationMailboxes, calendars, contacts and logs are stored on your servers.
Set your own policiesApply your own backup, retention and access rules.
Meet residency requirementsKeep data inside the jurisdiction your organization or customers require.

Easy Administration

Create mailboxes, manage domains, configure security and monitor service activity.

MailSite Console
MailSite 11 Console with server settings and domain navigation
MailSite ExpressPro browser workspace with folders, message list and reading pane

Full Featured Web Client for Email, Calendar and Contacts

Email, calendar, contacts, mobile synchronization, web access, centralized administration.

ExpressPro

Comprehensive Email Security

Built-in anti-malware and anti-spam capabilities, with administrative controls designed for teams operating their own mail environment.

Bayesian spam filteringBayesian filteringNative ClamAV integrationClamAV integrationTLS/certificate handlingSecurity documentation

Validation and Migration

Validate your exact client compatibility and workflows before production migration. Start with a pilot, test mail, calendars, contacts and shared access, agree acceptance checks, cutover and rollback before moving users.

Start a trial · Prepare your deployment · Plan your migration

MailSite vs. Exchange

Explore how MailSite and Exchange operating costs compare under an illustrative deployment model. Adjust the user count and review the assumptions for your environment.

Your annual estimates (USD)

Leave a field blank to use the illustrative estimate shown. Your entries are annual totals for the selected deployment and stay fixed when the user count changes. Clear them to restore the model.

The default Exchange license figure uses a historical Q&A estimate, not a reseller or Microsoft quote. Enter your own annual server, CAL and protection price for a purchasing comparison. Staffing defaults are planning assumptions, not measured requirements.

Compare with Exchange Server

Cost line itemMailSite SE Full SubscriptionExchange Server SE Standard$ Savings% Savings
License Cost $2,500$12,450$9,95079.9%
Hardware Cost $3,550$15,757$12,20777.5%
Administration Cost $6,200$12,400$6,20050.0%
Illustrative annual total$12,250$40,607$28,35769.8%

License cost assumptions

MailSite SE Full Subscription includes one year of anti-spam, anti-virus, calendaring, ActiveSync and MAPI subscriptions; its prices come from the online catalog’s full subscription SKUs. Microsoft requires a server license and user or device CALs for Exchange Server SE. The Exchange estimate uses $750 per server per year and $105 per user per year for Standard CALs, the midpoints of a Microsoft Q&A moderator’s rough ranges, plus $1 per user per month for anti-spam and malware protection. Exchange licensing varies by agreement; this is not a Microsoft quote.

Hardware cost assumptions

MailSite uses one continuously running AWS t3.xlarge Windows VM (4 vCPU, 16 GiB RAM); its release notes list an 8 GiB minimum. Exchange uses one r6i.4xlarge Windows VM (16 vCPU, 128 GiB RAM), following Microsoft’s recommended minimum for the mailbox role. Both include 5 GiB of gp3 storage per user. Costs use AWS’s instance rates, instance specifications, Windows license rate, and storage rate. Actual deployments must be sized separately.

Administration cost assumptions

This planning example uses a fully burdened annual cost of $155,000 per full-time administrator, including salary, benefits and overhead. At 500 users, Exchange assumes 0.4 full-time equivalent (FTE), or $62,000 per year; MailSite assumes 0.2 FTE, or $31,000 per year. Both scale proportionally for smaller user counts.

These are illustrative staffing assumptions, not measured requirements or guaranteed savings. Actual administration needs depend on your deployment.

Rates and estimates checked Q4 2026. Backups, bandwidth, redundancy, migration, taxes, Windows Server CALs, and other products are excluded. Ask Rockliffe for a quote above 500 MailSite mailboxes.

MailSite for your Business

Hosting Providers and MSPs

Deliver secure, scalable Windows email hosting built for shared and managed services.

For Hosting Providers

Keep Outlook and Simplify Your Messaging Environment

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View deployment options · Review deployment guide · Migration guidance · What's new in MailSite 11