There are standard headers like the subject, the sender or the recipient in the To: line. Another useful, but not so often used header is the Bcc: line. But why would you want to add another custom line?
Maybe you want to test an application that uses custom email headers as a standardized way to exchange information. Then you can use The Bat! to create any header you want the system to handle. Or, and I guess this is the more likely case, you can add custom lines to the email headers just for fun. How about a header that tells the recipient (if she is nosy enough to take a look at the email's source) which book you are currently reading? That would be the "X-Now-Reading:" header.
If you wonder where the "X-" comes from, let's take a look at what email headers are made of in general. All headers have a name and a value, separated by a colon. The subject header's name, for example, is "Subject", then comes the colon, and then the actual subject of the message, "Walking under water" for example. The complete header is "Subject: Walking under water" (empty spaces between the colon and the value are stripped when the header is parsed).
Now, there are a number of standard headers. The subject, sender, date, priority and recipients are some of them. But you can also invent any header you like, you just have to precede it with "X-" to make sure it does not conflict with any of the standard headers. Of course, you don't have any guarantee that nobody else has the same header idea, or that anybody knows what your X-header is for.
In The Bat!, you can edit and display any header you like — as long as you have defined it.
Add Custom Header Lines to Emails in The Bat!
To add your own custom header lines to emails in The Bat!:
- Select Options | Preferences... from the menu.
- Go to the Messages | Message Headers category.
- Click Add.
- Type the desired name of your header under both the RFC Name and the Display this header field as fields.
- For the now reading header, type "X-Now-Reading", for example.
- Make sure Allow to edit this field in the Message Editor is checked.
- Click OK.
- Click OK again.
Since The Bat! does not allow you to specify standard values for extra headers, you have to make sure you can (and do) enter a value when you send a message:
- Create a new message in The Bat!.
- Select View from the menu.
- Click the desired custom header to make sure it is ticked.
- Enter a value in the header's field.
- You can find them below the standard To:, CC: and Subject: fields.
- If you do not see your custom header field immediately, scroll the header area down a bit.
- Continue editing and sending your message as usual.
