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SecureMail User Manual

A practical step-by-step guide for form owners. If you just want to know what SecureMail is, see the landing page; if you have a quick question, see the FAQ.

Contents

  1. What is SecureMail?
  2. 1. Register your email
  3. 2. Place the form URL on your site
  4. 3. Receive and read messages
  5. 4. Use My Page
  6. 5. Spam protection (in detail)
  7. 6. Change email or cancel
  8. 7. Troubleshooting

What is SecureMail?

SecureMail is a free service that gives you a private contact-form URL you can embed on any website. Visitors send you messages via that URL without ever seeing your email address. You receive a notification email and can read the message in a private read-page or via My Page.

It is operated by Kodama & Co. and has been running since 2005.

1. Register your email

Registration takes about 60 seconds and requires no password.

  1. Open the landing page. In the "Get started" section at the bottom (or the hero form at the top), enter your email address.
  2. Click Send confirmation email. We immediately email you a confirmation link valid for 1 hour.
  3. Open the confirmation email and click the link. The link takes you to a page that shows your dedicated form URL:
    https://ssl.kodama.com/securemail?id=<22-character ID>
  4. Copy this URL. This is the URL you will embed on your website.
Tip: if the confirmation email doesn't arrive within a few minutes, check your spam folder — the sender domain is kodama.com. Some providers route automated mail there.

2. Place the form URL on your site

The form URL is just a normal HTTPS link. Wrap it in an <a> tag anywhere on your page.

<a href="https://ssl.kodama.com/securemail?id=abc123...">
  Contact me securely
</a>

Common placements: site footer, "Contact" page, sidebar widget, blog post end-line, business card or email signature.

Important: Do not change the URL or the ID. The 22-character ID is permanent and tied to your account; if you alter it the form will return an error.

Embed it as a button (optional)

<a href="https://ssl.kodama.com/securemail?id=abc123..."
   style="display:inline-block; padding:.6rem 1.2rem;
          background:#1a6ee0; color:#fff; border-radius:4px;
          text-decoration:none;">
  Contact me
</a>

Lost your URL?

Sign in to My Page with the same email you registered with. Your form URL is shown on the dashboard with a one-click copy button.

3. Receive and read messages

When a visitor sends a message you have two ways to read it.

A. Notification email

SecureMail sends a notification email to your registered address. The email contains a private read-link such as:

https://ssl.kodama.com/readmsg?id=...&msg=...

Click the link to open the message in your browser. The first click marks it as read.

B. My Page

Sign in to My Page to see all received messages in chronological order with unread badges. Click a row to read the full message. This is the recommended way to review history or read messages on devices where the notification email is hard to access.

Tip: Both ways work in parallel. You can keep receiving notification emails and still browse history from My Page whenever you want.

About the "Source page" field

Each received message may show a Source page — the URL of the page on your site (or anywhere else on the web) that the visitor was looking at when they opened your form. It is useful for traffic analysis ("which of my pages drives the most inquiries?") and for spotting where spam is coming from.

Next to the URL you will see (unverified). This means the value is reported by the visitor's browser and we do not independently confirm it. A casual user cannot fake it, but a technically skilled sender — or a bot — can put any URL there, including a URL that has nothing to do with where they really came from.

Treat the Source page as a hint, not as evidence. Do not click it unless you recognize the domain and trust it. It is shown as plain text (not as a clickable link) on purpose, to avoid accidentally sending you to a malicious site.

4. Use My Page

My Page is a self-serve dashboard at /mypage/. No password.

Signing in (magic link)

  1. Open /mypage/login and enter your registered email.
  2. We email you a sign-in link valid for 15 minutes.
  3. Click the link. You are signed in and see your dashboard.

Sessions last only for the current browser session. Closing the browser signs you out. Sign back in any time with one email.

What you can do

Page What it does
Dashboard (/mypage/) See your form URL with a copy button, unread message count, total volume.
Messages (/mypage/messages) Browse received messages in date order. Unread badge. 50 per page. Click a row to read in full.
Spam (/mypage/spam-folder) Messages caught by your block list. Restore false positives, delete the rest. See section 5.
Spam Settings (/mypage/spam-blocklist) Edit the block list (sender addresses, domains, keywords). See section 5.
Export (/mypage/export) Download all messages as CSV (UTF-8 BOM). Opens directly in Excel, Google Sheets, Numbers.
Account (/mypage/account) Change your registered email. See section 6.
Cancel (/mypage/cancel) Cancel your account. See section 6.

5. Spam protection (in detail)

SecureMail blocks spam in two layers. The automatic layer blocks bots before they can submit anything (no setup needed). The manual layer lets you block specific senders, domains, or keywords yourself — for the persistent sales emails and solicitations that bots can't catch.

5.1 What gets blocked automatically

Honeypot field + IP rate-limit run on every submission. They catch automated bot submissions without you doing anything.

Anything caught at this layer is silently discarded — it never appears anywhere, not even in the Spam folder. There is no false-positive risk because both checks rely on machine-only behaviours.

5.2 The Spam Settings page

Open Spam Settings. You see two text boxes.

5.3 Sender block list (top text box)

Enter one entry per line. Each line is interpreted as either an email address or a domain.

You enter What gets blocked Example use case
spammer@gmail.com Only that exact email address. One persistent individual using a free email account.
example.com All addresses at example.com AND any subdomain (e.g., aaa@mail.example.com too). A whole company sending you sales pitches.
@example.com or .example.com Same as above. We accept these as a convenience — the leading @ or . is stripped. Same.
One-way subdomain rule: registering a parent domain (bbb.com) blocks all its descendants (aaa.bbb.com, x@aaa.bbb.com, etc.). Registering a subdomain (aaa.bbb.com) does not block the parent (x@bbb.com). Always register from the "broadest scope you want to ban" downward.

5.4 Keyword block list (bottom text box)

Enter one keyword per line. Any message whose subject or body contains that keyword is blocked. Matching is case-insensitive and handles full-width / half-width characters automatically (so UNSUBSCRIBE, unsubscribe, and UNSUBSCRIBE all match).

Common useful keywords for stopping sales spam:

Caution: Keywords are powerful but can cause false positives (a real visitor might use the word legitimately). Only add keywords you're confident no real inquiry would contain. Start with one or two and watch the Spam folder for a week before adding more.

5.5 What happens when a message is blocked

  1. The message is not deleted; it is moved to your Spam folder.
  2. You receive no notification email. (The folder is the only place to find it.)
  3. The sender sees a normal "message sent" screen. They can't tell they've been blocked.
  4. The message is automatically deleted 30 days later.

5.6 The Spam folder

Open /mypage/spam-folder. You see a list of blocked messages with the reason each was blocked (which address, domain, or keyword matched).

You can:

5.7 Recovering a false positive

  1. Open the message in the Spam folder.
  2. Click Not spam (restore to inbox).
  3. If the block was caused by an entry still in your block list, the dialog asks whether to remove that entry too. Check the box if you want the same sender to come through next time as well.
  4. The message reappears in your normal Messages list as unread.
Note: If a message matched multiple entries (e.g., both your sender block list and your keyword list), removing only one entry won't fully unblock the sender. They may be re-blocked on the next submission by another rule.

5.8 Recommended starter setup

If you're brand new, here's a conservative starting point that catches the obvious and risks no false positives:

6. Change email or cancel

Changing your registered email

  1. Sign in to My Page → Account.
  2. Enter the new email address. We send a confirmation link to the new address.
  3. Click the link to apply the change.
  4. The old address receives a notification email so you'd notice if someone else triggered the change.

Cancelling your account

  1. Sign in to My Page → Cancel.
  2. Confirm. Your account is immediately closed.
  3. For 30 days the data is held in a grace period. If you change your mind, register again with the same email and everything (account, message history, block list) comes back.
  4. After 30 days the data is permanently deleted and cannot be restored.
Tip: Before cancelling, export your messages from /mypage/export to keep a local CSV copy.

7. Troubleshooting

"My confirmation / sign-in / notification email never arrived"

"My visitors say the form won't submit"

"A real inquiry was filed as Spam"

Open the Spam folder, click the message, click "Not spam (restore to inbox)". The dialog offers to remove the block list entry that caused it.

"I want to start over"

Cancel the account from /mypage/cancel. Within 30 days you can re-register with the same email; after 30 days you can re-register fresh with no history.

I can't find what I need here

See the FAQ or contact us through our own form: SecureMail contact form.

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