Connect your IONOS mailbox to Claude or ChatGPT (MCP)
Short answer: IONOS (formerly 1&1) has no AI connector and no MCP server for its mailboxes, but they use standard IMAP/SMTP. Add yours to MailMCP with imap.ionos.fr (port 993) and smtp.ionos.fr (port 465), your full address and the mailbox password, then paste your MailMCP server URL into Claude or ChatGPT. About 3 minutes.
Why an IONOS mailbox needs an MCP bridge
Many businesses got their domain and their email from IONOS (1&1), with Mail Basic or Mail Business. Claude and ChatGPT can only plug natively into Gmail and Microsoft accounts, so an IONOS address stays out of reach. MailMCP connects to it over IMAP/SMTP, like a mail app would, and turns it into an MCP server.
Without MailMCP
- No IONOS connector in Claude or ChatGPT
- No MCP server published by IONOS for its mailboxes
- Copy-pasting emails into the AI by hand
With MailMCP
- Your IONOS mailbox becomes an MCP server with its own URL
- Emails sent from your own address, through smtp.ionos.fr
- Works with Claude, ChatGPT, Cursor, n8n, Make and any MCP client
IONOS IMAP/SMTP settings
Settings for Mail Basic and Mail Business mailboxes under a French IONOS contract.
IMAP — Incoming mail
- Server
- imap.ionos.fr
- Port
- 993
- Security
- SSL/TLS
- Username
- your full email
SMTP — Outgoing mail
- Server
- smtp.ionos.fr
- Port
- 465 (or 587 STARTTLS)
- Security
- SSL/TLS
- Password
- the mailbox password
Contract outside France? IONOS uses server names by country: its English help lists imap.ionos.com and smtp.ionos.com (US contracts), and German contracts use imap.ionos.de. Old 1&1 server names found in older tutorials should be replaced by the IONOS names.
Sources: IONOS help (« IONOS Mail: Server details for IMAP, POP3, and SMTP », « What restrictions apply to sending bulk emails? ») and IONOS Assistance France (« Tester l'accessibilité des serveurs de messagerie avec ping »), checked on October 18, 2026.
Connect your IONOS mailbox in 3 steps
About 3 minutes.
Create your MailMCP account and type your address
Sign up for free, no credit card. In the dashboard, click « Add a mailbox » and type your IONOS address, for example firstname@mydomain.fr, then « Continue ».
Replace the suggested servers with the IONOS servers
MailMCP does not recognise IONOS from your address, so the wizard shows the server fields, pre-filled with mail.yourdomain, which usually does not point to IONOS. Enter imap.ionos.fr as IMAP server and smtp.ionos.fr as SMTP server, then the mailbox password, and click « Next — Test connection ». For SMTP, MailMCP tries 465 in SSL, then 587 in STARTTLS if 465 does not answer.
Connect Claude or ChatGPT
Once the test passes, MailMCP shows the MCP server URL of this mailbox. Add it as a custom connector in Claude, or as an app in ChatGPT developer mode, and sign in to MailMCP when asked.
Your MCP server URL:
https://mailmcp.io/mcp/mcp_xxxxxxxx
Illustrated guide: connect Claude · Illustrated guide: connect ChatGPT
IONOS pitfalls and how to fix them
« Authentication failed »: customer password instead of mailbox password
The password of your IONOS customer account does not open the mailbox. Use the password of the email address itself; if you no longer have it, change it in your IONOS customer area, E-mail section, on the address. Then update it in MailMCP on the mailbox page (Connection tab).
« Mail server not found » or timeout
The wizard's mail.yourdomain suggestion was left in place, or a typo slipped in. Enter exactly imap.ionos.fr and smtp.ionos.fr (or the names for your contract's country), then test again.
« 450 Mail send limit exceeded » on a new mailbox
IONOS caps sending per hour on Mail Basic and Mail Business according to the age of the address: 50 emails an hour for the first 7 days, 100 from day 8 to 14, 400 from day 15 to 30, then 500. If your AI sends a batch from a brand-new address, spread the emails out or schedule them.
Microsoft 365 bought from IONOS
If your IONOS email is in fact Microsoft 365, it is a Microsoft mailbox: imap.ionos.fr will refuse it. MailMCP recognises it from your domain's mail servers and shows « Sign in with Microsoft »: no password to type.
Emails sent by the AI land in spam
The MailMCP diagnostic checks your domain's SPF, DKIM and DMARC when you add the mailbox and tells you what is missing. Fix the records in the DNS of your domain (at IONOS if the domain is registered there).
What your AI can do with your IONOS mailbox
16 email tools: your emails are read on demand on the IONOS server, never stored by MailMCP.
Read, search, sort
Summaries of unread emails, search by sender or subject, folders, flags, read or unread.
Send with attachments
Replies and new emails sent from your address, with attachments (link, upload or inline image; 10 MB per file, 25 MB per email).
Schedule
Emails scheduled for later, listed and cancelled on request. Every action is kept in the MCP log for 30 days.
Example requests
- « Find the unpaid invoice reminders received this month and list them by client. »
- « Reply to Martin's quote request, attach the PDF from this link and send it tomorrow at 8 am. »
MailMCP vs the native email connectors
| MailMCP | Claude connectors (Gmail, Microsoft 365) | ChatGPT connectors (Gmail, Outlook) | |
|---|---|---|---|
| IONOS mailbox (Mail Basic, Mail Business) | Yes | No | No |
| Attachments in sent emails | Yes | No | No |
| Scheduled sending | Yes | No | No |
| Log of every action | Yes, 30 days | No | No |
The native connectors do read and send email, but only for Gmail and Microsoft accounts. Detailed comparison with the Gmail connectors
Sources: Claude help center, OpenAI release notes (June 8, 2026), MailMCP tests (October 2026).
Frequently asked questions
What are the IMAP and SMTP settings for IONOS mail?
imap.ionos.fr or imap.ionos.com?
Do I need an app password for IONOS?
Does it work with IONOS Mail Basic and Mail Business?
Why can't I connect IONOS to Claude or ChatGPT without MailMCP?
Is it free?
Give your IONOS mailbox an AI assistant
Free account, hosted in France. Your IONOS mailbox in Claude, ChatGPT or Cursor in a few minutes.
