Connect @nifty mail to Claude,
Cursor, ChatGPT, any MCP client
Give your AI agent a real nifty.com inbox. Read, search, send, reply, schedule and organize mail over IMAP, once the IMAP connection permission is on and you have the mail password @nifty issues for mail software.
Claude cannot reach @nifty mail on its own. MCPEmails is a hosted MCP server that connects it over IMAP at imap.nifty.com on port 993, authenticating with your full @nifty address and the @nifty mail password, so Claude, Cursor or any MCP client can read, search, send and organize that mail. Two things decide whether the login works, and @nifty documents both: a setting called メールソフト接続許可（IMAP） has to read 許可中 in your mail settings, and the password has to be the dedicated mail password, not the one for your @nifty ID. One inbox is free, forever.
How @nifty connects: IMAP, a permission, and a password made for mail software
@nifty documents IMAP at imap.nifty.com on port 993 with SSL/TLS, and SMTP at smtp.nifty.com on port 465 with SSL/TLS and SMTP authentication required. The username is the full address, and the authentication method on both is ordinary password authentication, which @nifty's guide labels 通常のパスワード（PLAIN/LOGIN）. The password is the メールパスワード, a credential @nifty issues specifically for mail software; if you do not know it, the guide says to set a new one on the password change page. Before any of that works, the setting メールソフト接続許可（IMAP） in your mail settings list has to show 許可中. For a standard address it sits under @niftyメール; for add-on mailboxes it sits under セカンドメール/セカンドメールPRO/旧Infoweb追加アカウント. Do not rely on a mail client to fill this in: the public autoconfiguration database still describes @nifty as unencrypted POP on port 110, which is wrong on every count.
The exact @nifty IMAP and SMTP settings
Copy these into the connect form. MCPEmails prefills them where it can, and retries the other standard transport if the first does not answer.
| Protocol | Server | Port | Security |
|---|---|---|---|
| IMAP (incoming) | imap.nifty.com | 993 | TLS (implicit) |
| SMTP (outgoing) | smtp.nifty.com | 465 | TLS (implicit) |
Verified 2026-11-04: imap.nifty.com answered a TLS connection and identified itself as an IMAP server under that name. It advertises CRAM-MD5 authentication.
Sign in with: Your full @nifty address, for example abc12345@nifty.com, as @nifty's own guide shows it.
A @nifty inbox your agent can actually use
21 action-based MCP tools: send, reply, forward, schedule, and organize. Your agent finishes the job inside @nifty.
- 01Read
Read & search mail
List, read and search across folders to find that invoice, summarize a thread, or pull the latest from a sender.
- 02Send
Send, reply & forward
Compose and send real messages, reply in-thread, and forward, directly from your mailbox, not as a draft you finish by hand.
- 03Schedule
Schedule for later
Queue a message to go out at the right time, so your agent can draft now and send on schedule.
- 04Organize
Move, copy, flag, archive, delete
Keep the inbox tidy: file mail into folders, flag what matters, archive the rest, or delete on request.
Connect @nifty in four steps
From sign-up to first AI email in a couple of minutes.
Create your free MCPEmails account
Sign up at mcpemails.com. The free plan connects one inbox forever and asks for no card. Leave it open; the @nifty side takes a couple of minutes.
Set the IMAP connection permission to 許可中
In your @nifty mail settings list, find メールソフト接続許可（IMAP） and make sure it reads 許可中. For a standard account it is under @niftyメール; for a second or add-on mailbox it is under セカンドメール/セカンドメールPRO/旧Infoweb追加アカウント. Until this is on, every IMAP login is refused.
Enter the full address and the mail password in MCPEmails
Choose IMAP / SMTP, enter the complete address such as abc12345@nifty.com, and paste the @nifty mail password. If you do not know the mail password, set a new one on @nifty's password change page first. The hosts and ports are prefilled and were confirmed from a live TLS connection.
Paste the MCP URL into your AI client
Drop https://mcpemails.com/api/mcp into Claude, Cursor or ChatGPT, authorize, and your agent can read, search, send, reply, forward, schedule and organize the @nifty mailbox.
Step-by-step guides: How to connect Claude to your email · Claude IMAP connector guide
More guides: Custom connectors in Claude, explained · Schedule an email from the chat
Use this inbox in your AI app: Claude · ChatGPT · Cursor · VS Code · Codex · Claude Code · Cline · Windsurf · Gemini CLI · All supported apps
Need the server names and ports? Look up IMAP and SMTP settings
Comparing providers first? See the email provider compatibility matrix
Use @nifty in ChatGPT
ChatGPT reaches @nifty through a custom MCP server, which you add on chatgpt.com with ChatGPT Go or a paid plan.
- Connect @nifty to MCPEmails with the steps above.
- On chatgpt.com, open Plugins, Personal, click Add, then Add custom MCP server.
- Name it MCPEmails, paste
https://mcpemails.com/api/mcpunder Connection, choose OAuth, confirm, click Create as a plugin and sign in to MCPEmails. - In a chat, type @ and pick MCPEmails. Do it again when a follow-up needs your mail.
What actually goes wrong with @nifty
The permission and the password fail identically
A login refused because メールソフト接続許可（IMAP） is off looks exactly like a login refused because you pasted the @nifty ID password instead of the mail password. The server returns the same authentication error for both and names neither. Check the permission first, since it is the one that ships off, then confirm you are using the mail password rather than the ID password. @nifty issues the mail password separately precisely so that mail software never holds the ID credential.
Before login the server offers only CRAM-MD5
The capability list imap.nifty.com returns before authentication names a single mechanism, AUTH=CRAM-MD5, and no SASL-IR. @nifty's own guide nonetheless tells you to choose ordinary password authentication, and the capability list carries no LOGINDISABLED, so the plain IMAP LOGIN command stays available over SSL. Client libraries that only authenticate through an advertised SASL mechanism, and do not implement CRAM-MD5, stop before they ever send credentials, which is why some IMAP tooling reports @nifty as unreachable while Outlook and Thunderbird connect to the same mailbox. MCPEmails handles the bare LOGIN path.
English folder names, a 50-folder cap, and two folders that do not move
@nifty's IMAP guide names the special folders Draft, Sent and Trash, and says the archive and IMAP path prefix should stay blank. Because the server advertises no SPECIAL-USE, those names are how MCPEmails finds them. The same guide sets a limit of 50 folders in the webmail and in mail software, says that folders created in the webmail may have to be shown manually in a mail program, and notes that mail in the Sent and Draft folders cannot be moved out of them and nothing can be moved in. An agent asked to file a sent message somewhere else will be refused by the server, not by us.
Autoconfiguration data for @nifty is stale and would set you up unencrypted
The public Mozilla database describes nifty.com as plain POP3 on port 110 with SMTP on 587, a configuration @nifty no longer documents. A client that fills in settings from that source gives you an unencrypted download-only account, not the IMAP mailbox @nifty publishes. Enter imap.nifty.com, port 993 and SSL/TLS by hand, or let MCPEmails prefill them.
Known limits with @nifty
- The mailbox allows 50 folders at most, and messages in the Sent and Draft folders cannot be moved to other folders. Both limits are enforced by @nifty.
- There is no IDLE support, so mail is polled rather than pushed. Your agent sees a new message the next time it checks rather than the moment it arrives.
- The SMTP server accepts messages up to 20 MB. A forward carrying larger attachments is refused at send time.
@nifty and AI: common questions
Does Claude work with @nifty mail?
Not on its own. Claude has no built-in @nifty connector and cannot open an IMAP connection by itself. Connecting an MCP server such as MCPEmails to the mailbox over IMAP gives Claude read, search, send, reply, forward, schedule and organize access to it, and the same connection works from Cursor, ChatGPT and other MCP clients.
What are the @nifty IMAP and SMTP settings?
IMAP is imap.nifty.com on port 993 with SSL/TLS. SMTP is smtp.nifty.com on port 465 with SSL/TLS and authentication. The username is your full @nifty address and the password is the @nifty mail password. Both hosts were confirmed from a live TLS connection on the date shown on this page.
Why is my @nifty password rejected by a mail app?
Either メールソフト接続許可（IMAP） is not set to 許可中 in your mail settings, or you entered the @nifty ID password instead of the dedicated mail password. Check the permission first. If you do not know the mail password, set a new one on @nifty's password change page and use that.
Where is the IMAP connection permission in @nifty?
In the mail settings list. For a standard address it is under @niftyメール; for a second or add-on mailbox it is under セカンドメール/セカンドメールPRO/旧Infoweb追加アカウント. The setting is called メールソフト接続許可（IMAP） and has to read 許可中.
Does @nifty need an app password?
Not in the Gmail sense, but it does use a dedicated credential: the @nifty mail password, which is separate from the @nifty ID password and is the one mail software must use. There is no per-app token.
Is my @nifty mail stored on your servers?
No. Messages are fetched live from @nifty over IMAP for each request and passed to your AI client. Credentials are encrypted at rest and message bodies are not retained.
Can ChatGPT read my @nifty mail?
Yes, once @nifty is connected to MCPEmails. On chatgpt.com, add a custom MCP server with the URL https://mcpemails.com/api/mcp and OAuth sign-in. That works with ChatGPT Go and paid plans. ChatGPT gets only the access you approve, and your mail is fetched live, never stored.
Give your AI an @nifty inbox
Connect @nifty mail in minutes once the IMAP permission is on. One inbox free forever, no card required.