AI for your Exchange Server On-Premises.
Postgate AI connects your Microsoft Exchange Server (on-premises and hybrid) to Claude, ChatGPT, Perplexity, Gemini, Mistral Vibe, and any MCP-capable AI assistant.
- Managed in Germany or self-hosted
- Individual permissions per employee
- Open standard (MCP)
How Postgate AI connects Exchange On-Premises to AI assistants.
Microsoft 365 Copilot requires Exchange Online. For Exchange Server in your own data center, Microsoft offers no comparable connection. That is exactly what Postgate AI was built for.
- Exchange Serveron your premises
- Postgate AIMCP server, set up once centrally
- AI assistantof your choice
Everyone works with their own mailbox and exactly the permissions they have in Outlook.
Optional extra: the add-in right inside OutlookEmails, appointments, contacts, and tasks: in chat, through agents, and in your own workflows.
AI chat
Your mailbox in natural language: ask, search, write, schedule meetings, on desktop and mobile.
Autonomous agents
Assistants running around the clock: triage mail, draft replies, flag follow-ups.
Any automation
Connect your own workflows and agent platforms via the open MCP standard and automate what you need.
What you can do with it
Meeting times in seconds, no email back-and-forth
Just ask for a time that works for everyone. Postgate AI checks all attendees' calendars, suggests open slots and sends out the invite if you want.
Reply to Claude…
Your morning briefing, ready before your day begins
A daily summary of your mailbox: what's new, what matters, and who's been waiting days for a reply, with priority and subject line.
Ask anything
Remembers your out-of-office, before you do
The AI spots the vacation in your calendar with no out-of-office set, and proactively drafts a ready-to-use reply. One tap and it goes live.
The assistant works in Outlook, right next to the open e-mail
The optional add-in opens a task pane in classic Outlook for Windows and in Outlook for Mac. The assistant relates your question to the open e-mail and works with your own permissions, including with Exchange on-premises.
More about the Outlook add-inHelen Ashcroft Quote for 40 seats - questions on term length
08:12Good morning James,
thank you for the quote you sent on Monday. We discussed it in the management meeting and there are three points to settle before procurement takes over:
1. You priced 40 seats. After the new site plan we are closer to 52, twelve of them in Leeds. How does that change the volume discount?
2. Procurement considers a 36 month term too long. Is 24 months possible, and what does it add per seat?
3. The works council wants to know where the data is stored and who can see it. A short written statement would help us a great deal.
Postgate AI
Mailbox assistant
Context: open e-mail
Ask about your mailbox…
Built for Exchange On-Premises, with each employee’s own permissions.
For self-hosted Exchange
Connects your Exchange Server in your own data center, including hybrid environments. No cloud mailbox required.
Individual permissions per employee
Everyone keeps their existing Exchange permissions, unchanged. Every access is personal and encrypted, and no one can see anyone else’s mailbox. No service account with access to all mailboxes, no master key.
Server-side, around the clock
Runs centrally on the server, at night too, even when your PC is off. For chat and automation.
Open standard (MCP)
You choose the AI assistant freely. Claude today, ChatGPT tomorrow.
One central server, no installation on any client.
Each customer gets a hardened, dedicated instance.
Delegated, isolated, encrypted
Delegation instead of impersonation, per-user encrypted vault, cross-user isolation.
Verified identity
OAuth 2.0 / PKCE, self-service onboarding via Microsoft sign-in.
Open integration
The MCP standard over Streamable HTTP, for any MCP-capable client with OAuth support, including Microsoft Copilot Studio and n8n as agent platforms.
Compliance
GDPR-compliant, DPA available.
Operated by us or on your own Windows Server.
The mailbox tools are the same in both models. Setup, sign-in and licensing differ.
Managed by us
A hardened, dedicated instance run by us in Germany, set up once and ready immediately. We operate, patch, and monitor the server for you.
See pricing →Self-hosted
Runs as a service on a Windows server of your own in your network. Operations, data and keys stay with you. Price on request.
More on self-hosted →AI supports you in everything you do in Outlook and makes your working day easier.
Mailbox
- Calendar
- Contacts
- Tasks
- Folders
- Search
- Attachments
- Shared mailboxes
- Bulk actions
AI assistance
- Rules
- Follow-ups
- Approvals
- Out of office
- Briefings
- Memory
- Writing style
Frequently asked questions
Does Copilot work with on-premises Exchange?
No. Microsoft 365 Copilot requires a mailbox in Exchange Online. For self-hosted Exchange Server (on-premises), Microsoft has so far only published an interest survey, no product. Postgate AI closes exactly this gap, available today. You need neither Microsoft 365 nor a Copilot license for it. More on this on the "Microsoft Copilot & Exchange On-Premises" page.
Do our emails leave the company?
Yes, for processing: requests and responses pass through our server in Germany, GDPR-compliant, with a DPA. We operate like a transparent proxy. By default we do not store or log mailbox content. We do not run an AI of our own. You decide which AI model processes your content. If you run Postgate AI yourself, processing runs through your own server.
Why do I have to sign a data processing agreement (DPA)?
Because Postgate AI processes data from your mailboxes on your behalf, the GDPR (Art. 28) requires a data processing agreement (DPA) between you and us. Signing is part of registration and takes one click, our subprocessors are listed in it.
Does every employee need new permissions?
No. Existing Exchange permissions apply, unchanged. No new permission model, no shared account.
Which Microsoft Exchange versions are supported?
Microsoft Exchange Server Subscription Edition (SE), Exchange 2019, and Exchange 2016 via EWS, including versions whose Microsoft support ended in October 2025. Hybrid environments are supported as well.
Can we self-install Postgate AI on our own server?
Yes. A self-hosted license runs as a service on a Windows server of your own in your network. Operations, data and keys stay with you. Price on request; more on the "Self-hosted" page.
Which AI tools work with it?
Claude, ChatGPT, Perplexity, and Mistral Vibe are fully supported; Gemini via Gemini Enterprise or Google Antigravity; Microsoft Copilot Studio and n8n as agent platforms. Plus any MCP-capable client with OAuth support, including your own agents.
What is MCP?
The Model Context Protocol: an open standard that lets AI assistants securely access external systems such as your mailbox.
What does the 2026 EWS retirement mean for us?
It only affects Exchange Online. On-premises Exchange keeps EWS, exactly the interface Postgate AI connects through.
Want to see Postgate AI in action?
Try Postgate AI free for 14 days with your own mailbox. No credit card, ends automatically.