Category Archives: Shadowmail

View headers and retrieve email from separate email accounts

Shadowmail and Checking Gmail Accounts

“Shadowmail” is a service for Sailmail members which monitors a separate email account via POP3 access. For basic information about Shadowmail see this page: or send a (blank) email to:

This page describes how to use Shadowmail with Google’s Gmail accounts. Gmail POP3 email access is a bit “quirky” (some would say “distinctly odd”). The three great things about Gmail are that it is free, you get lots of space, and of course Gmail has great search tools for archived email. The “quirky” part is that Google is very strict about security, and also –depending on your GMail settings — POP3 can try to forward everything in your Gmail account, not just recent mail in your “inbox”. That is a problem if you have a large number of archived messages in your Gmail account (which may be the whole point of Gmail). If you pick the wrong option in setting up GMail’s POP3 access, then Shadowmail will try to send headers for all of those messages. This is bad, so please read the notes below on using the “recent:” prefix.

Setting up Shadowmail access for GMail involves three steps:

  1. Enabling POP3 access via settings in your Gmail account;
  2. Entering your Gmail login info into Airmail’s Shadowmail settings; and
  3. Resolving any security or access issues.

One caution: Do this when you have internet access, and be sure that your internet connection allows Airmail to access Sailmail directly. See this page for more info: or send a (blank) email to:

Step 1: Setting up Gmail for POP3 access:

First, you need to enable POP3 access from Gmail. Go to your Gmail account, click “settings” (the “gear” icon in the upper-right), then “See all settings”, then select the “Forwarding and POP/IMAP” tab.

In the “POP Download” section you can enable POP access either for “all mail (even mail that’s already been downloaded)”, or “only for mail that arrives from now on”. The first “all mail” choice is the equivalent of Gmail’s “All Mail” selection on the web, and shows all messages. IMPORTANT: If you select this, then use the “Recent:” login prefix– see below.

The second “from now on” selection is Gmail’s “Inbox”, which shows newly-arrived messages. The problem with this is that messages disappear from Inbox once they have been read, so if you are also checking mail from another device or the web page then Shadowmail won’t see them.

RECOMMENDATION: Select “All Mail”, and use the “Recent” prefix for your login.

In either case, select “Keep Gmail’s copy in the inbox”, it doesn’t matter for POP3 access but does affect how new messages are presented on the Gmail web page.

Step 2: Airmail settings for Shadowmail:

The basic Shadowmail setup for Gmail is the same as for any account: The server address is “” (without the quotes), the login name is your complete email address (with the “recent:” prefix), and the password is your Gmail account password. A secure connection is required via port 995 but Shadowmail handles that automatically.

IMPORTANT: If you did selected “all mail” in your GMail settings, then you should restrict POP3 access to only recent messages (less than 30 days old). Do this by adding “recent:” to your login name in your Shadowmail settings– for example  “” instead of “”– no spaces. This will cause Gmail to only show recent messages to Shadowmail, and older messages will be ignored.

Keep in mind that (no matter what options are selected) GMail’s POP3 access includes sent-messages which were sent from GMail’s web-page. Also, unless you are using the “recent:” login-prefix described above, messages which have been read via GMail, or retrieved via POP3, are NO LONGER included in the POP3 index- they will disappear from your Shadowmail folder, but are accessible via Gmail. However, if the “recent:” prefix is used, then all recent messages are available to Shadowmail. (Like we said, “quirky”).

Once you get your Shadowmail settings set up for your Gmail account, then connect to Sailmail (via internet, initially) and Airmail will send the settings message to the server. Shadowmail will immediately check your Gmail inbox, and you should get the initial batch of “new mail” messages. This will sync your Gmail “Shadow Folder” to your Gmail account.

Instead of a batch of “New Mail” messages, you may get an error message instead– have a look in “Shadow archive” folder under Airmail’s “Inbox”.

Use an “App Password” for Shadowmail:

Gmail previously allowed you to check email with your normal Google password, once a new device was authorized. This has become more difficult but may still work if you have recently updated your Google password. With an older password, Gmail will not allow access from a new device. So one option is to update your password. But a more reliable method is to get a special “App Password” for Shadowmail. However, Google only makes this available if “2-Step Verification” is enabled.

So the first step is to turn on “2-Step Verification” (if not already done).  This is now required in order to get an App Password. This also helps to protect your Google account. This means that you can only access your main Google account (including Gmail via the web) if you can also verify access with a second step: Either a smart-phone with internet access, or a simple cellphone capable of receiving text messages, or — most important for our needs– a list of one-time “backup Codes” printed on paper.

To learn more, and turn on 2-Step Verification, see this Google web page:

Once that is done, go to your Google account settings (under your icon in the upper-right), select “Security”, then “Signing In”, then “App Passwords”. For “Select App” click “Other”, enter “Shadowmail” and then copy the password shown (a 16-digit number, don’t include the spaces).

For more informal about App-Passwords see this web page:

Other security issues:

If you have entered the incorrect username or password then you will see:
“[AUTH] Username and password not accepted”. Check your username and password. If you are using an App Password then do not include any spaces.

Alternately you may have run afoul of GMail’s security checks, in which case you will see a message something like this:
Exception while connecting: [AUTH] Web login required:

That is stunningly unhelpful, but if you follow that link then you will get some vague advice about updating your email client (not applicable),  using App Passwords, or allowing “less secure apps”.

Allowing “less secure apps” means allowing access with a username and password. With a strong password and a secure connection (which Shadowmail uses) this is quite secure, the problem is that if your password gets stolen then that allows access to all of your Google accounts. Selecting “Allow less-secure apps” worked previously for POP3 access, but we could not make it work in our testing (mid-July 2021), and is also not available when 2-Step Verification is enabled. Therefore we recommend 2-Step Verification as the

Turning on “2-Step Verification” is a nuisance but is a reliable solution. Select as many alternate devices as you can, and if you have a security key then use that also.

And be sure to select “Backup-codes” and save that. This is a list of ten one-time codes that can be used to access your Google account (not Shadowmail). Cross them off once used, and get a new set after you’ve used a few.

Once you have sorted out your Google settings, you can trigger Shadowmail to check your account as follows:

  1. Open Airmail’s Shadowmail settings (Tools menu)
  2. UN-check the “Account active” box. This creates a new settings message.
  3. Connect to Sailmail (preferably via internet) to send the settings.
  4. Go back to Shadowmail settings and CHECK the “Account active” box.
  5. Connect again to Sailmail, to send the updated settings message.

This disables and then re-enables Shadowmail, and will trigger a new-mail check. Be sure to connect to Sailmail via internet each time, to send the updated Shadowmail settings message.

Wait a minute or two and check Sailmail again– you should have a batch of “new mail” messages.

As with other web-based email accounts, keep your Inbox tidy by archiving messages that you want to save and deleting the rest. Gmail does not provide separate archive folders but you can add labels which is basically the same thing.

Please note that this information is current as of late 2022, but internet security evolves rapidly and things change. Please send a note to support if you have problems and we will try to help sort it out.

Revised 2022-10-06 by Jim, Sailmail support

Shadowmail Overview: previewing and downloading email from other accounts

ShadowMail Info

“ShadowMail” provides a method of watching a separate email account, and for downloading or forwarding messages as needed. This is available only to Sailmail members, and without charge.

The purpose of Shadowmail is to act as a bridge between your Sailmail address and whatever other email address you might use for regular email. The great advantage of Sailmail of course is that it works pretty much anywhere, but connection speeds are slow whether via radio or satellite. This means that you need to keep your Sailmail address private, and limited to friends and associates who understand not to send jokes, spam, etc.

We strongly recommend maintaining some sort of regular land-based email address for routine mail, on-line ordering, etc. This can be a regular personal or company email account, or a Hotmail, Yahoo or Gmail address for “public” use. These folks will keep your low-priority mail forever (Hotmail and Yahoo may require a small annual payment for this) until you can check mail from an internet-cafe. The problem of course is that folks sometimes send important messages to your regular address, and you have no way of knowing. Enter the Shadow…

Once you set it up, the Shadowmail server checks your regular email account a few times a day and sends you a summary of whatever new messages have arrived. Airmail decodes those “new mail” messages to maintain a “shadow” folder for each regular email account, showing the contents of that mailbox as a separate Airmail folder. For example, assume that you set up Shadowmail to monitor your Hotmail account. Then in addition to the usual “Inbox” and “Outbox” folders in Airmail, you would also have a “Hotmail” folder with a gray icon instead of yellow, indicating a “shadow” folder. When you open that folder you see a list of messages which are currently pending in your Hotmail account, showing from- and to-addresses, subject and date.

If you want to download one of those messages via Sailmail then right-click on that message and select “retrieve”. If you want to forward it to someone else (without downloading it) then right-click on it and select “Forward”. If you want to delete it without ever reading it, then right-click and select “Delete”. If you go to the local cyber-cafe and read and delete some of the Hotmail messages, then they will be removed from Airmail’s shadow-folder on the next update. The Hotmail shadow-folder will always match the contents of the Hotmail “inbox”.

To use Shadowmail a current version of Airmail is required, and you must be a Sailmail member. Shadowmail can be used via a radio connection, or via internet or satphone using Airmail’s Internet window. The first step is to read this document carefully and make sure that you understand the limitations. By using Shadowmail you are agreeing to the conditions contained here, and to the Saildocs terms and conditions (

To set up Shadowmail to monitor an email account, first enable Shadowmail and open the “Shadowmail Settings” window. Start by opening Airmail’s Options window (from the Tools menu), and then click on the “Modules” tab. Check the box to the left of “Shadowmail” (if not already checked) and click the “Setup” button to open the settings window.

Initially this “Shadowmail Setup” window is empty, click “New” to create a new account. Then enter the server-address (the internet address of the “POP3” server), the login name and the password for the email account that you want to “shadow”. (This is NOT your Sailmail login, you need to get the server, login-name and password from the outfit that handles the email account that you want to monitor). Make sure “Account Active” is checked, and then click OK. Airmail will send a settings-message to the server and it will start monitoring your account. Mail is checked every 6 hours and you will get a message from the server (“”) whenever new mail is received into that account.

Shadowmail can check any POP3 mail account, such as a business or regular Internet account. The Internet provider will supply the server address, login name and password. Keeping your mailbox tidy will make it easier to keep track of things. A good technique is to wait until you have Internet access at a marina and then retrieve everything you want to save to Airmail and delete it from the server. Alternately you can forward messages from the Shadow folder to another account, such as Hotmail or Gmail for safekeeping.

Here is how some accounts are handled…

Hotmail/Outlook/Live: Hotmail provides secure POP3 access to all Hotmail/Windows-Live accounts. We would still suggest the “plus” service ($20/year), which provides more storage and avoids the account being deactivated if you don’t check it for a month or two. Use the server-name “”, “” or “” (without the quotes), use your complete email-address as the login name, and the same password that you use for web login. Since Shadowmail has to check everything in your Inbox folder whenever it checks mail, it is important to keep things tidy by moving messages that you want to save into “archive” folders and deleting the rest. Create new folders for specific topics (or by year, for example) and move messages that you want to save into those folders for safekeeping after you have reviewed them.

Yahoo: For Yahoo accounts you will also need the “plus” service ($20/year) to allow POP3 access. This also provides additional storage and avoids deactivation. Use the server-name “”, the login name is your Yahoo user-name without “”, and your Yahoo account password. Again, keep your inbox tidy by moving messages that you want to keep into other folders, and deleting the others.

Google GMail: Shadowmail can also check GMail accounts, but GMail is a little “quirky”. Here are the recommended settings, send a (blank) email to for more info (or see You will need Internet access to set this up, to access your GMail settings.

First, log into your GMail account, click on the “Gear” icon (upper-right) and select “Settings”. Next click on Forwarding and POP/IMAP”, find “POP Download”, and select “Enable POP for all mail (even mail that’s already been downloaded)”.

Next, click on “Accounts and Import”, and under “Change account settings” click on “Other Google Account Settings”. This opens a new security page, on the left click on “Connected apps & sites”. Scroll down and find “Allow less secure apps: and set that to “ON”. (It is still quite secure, see the “shadow-gmail” note referenced above for more detail).

Now go back to Airmail’s Shadowmail settings and create a new account for “GMail”. For server-address enter “”, for login name enter “recent:” (without the quotes) followed by your complete GMail email-address (i.e. “”), and for password enter your normal GMail password.

The three great things about Gmail are that it is free, you get lots of space, and of course good search tools for archived email. The “quirky” part is that POP3 can access everything in your GMail account (not just your “inbox”). Without the “all mail” setting (above) then messages “disappear” unexpectedly from POP3, and without the “recent:” prefix then Shadowmail would have to sort through the entire archive– which can exceed its capacity. Using the “recent:” prefix, in conjunction with selecting the “all” selection in GMail’s POP settings, gives Shadowmail access to all recent messages.

AOL: AOL has added POP3 access and Shadowmail can check AOL accounts. The server is “”, the login-name is your AOL “screen name”, and the password is your AOL login password. The server may occasionally return a “timeout” error, double-check the server-name and don’t worry, Shadowmail will keep trying.

For any email account, if you get back an error-message then double-check the POP3 server-address. Make sure the login name is correct, sometimes it is just your email name, or it may be the complete email address, or perhaps something completely different. Check the support information for the folks who provide the account, they will need to supply that info.

You can also set up Shadowmail rules that will forward specific messages to your Sailmail address whenever they are received. For example, you can set up Shadowmail to forward anything with “urgent” in the Subject-line, and then give your business-associates your Hotmail address and tell them to include that word in the message-subject if they need an immediate reply. They don’t have your Sailmail address, but you can still be in touch- and in control. These “rules” are part of Airmail’s Shadowmail settings window, and can include two different checks, for example sender contains “mom” and size less-than 2000.

Replies that you send for messages which were retrieved by Shadowmail will of course be sent via Sailmail’s servers, and would normally come from your Sailmail address and with the how-to-reply footer added to the bottom. However if you are replying to a message which was retrieved via Shadowmail, then Airmail should substitute that reply address. Check this, however, and if you don’t see the “From” box in the message header then select the Message Menu, “Show From-Box”. A new box appears, enter the address that you want your email to be sent from.

Also, to suppress the Sailmail footer, add a line at the bottom of your message which says “short-footer” (without quotes) for a one-line footer “radio email processed by SailMail” and web-address) or “no-footer” for no footer at all. This should be on the last line, by itself, without quotes.

Some caveats and limitations: Shadowmail normally only sends a notice for new messages, not the entire mailbox. But when the account is first set up then the whole mailbox is indexed, this can be large. If you have a lot of pending messages then try to do this via internet, not radio. Also, remember that the Shadowmail server must download the index for the entire mailbox whenever checking mail, this gets time-consuming if there are a lot of pending messages. The current limit is 1,000 pending messages, this may be adjusted up or down if needed. It is convenient to use the web-based mailboxes (Hotmail, Yahoo, GMail, etc.) as message-archives, but move messages to other folders and don’t keep them in the “inbox”. You won’t be able to use Shadowmail if there are too many messages in the inbox.

Also be careful and selective about setting up an automatic retrieval, and never set up Shadowmail to retrieve everything. Remember that the headers are always sent, and you can retrieve any message- the only reason for automatic retrieval is for messages that you are sure you want, so be selective.

Saildocs is a service of the Sailmail Association. For more information about Saildocs, send a (blank) email to: (or see the website at

Please send questions about Shadowmail or Saildocs to:

Good sailing, Jim

(updated 2016-02-05)