Maccast Members #168 - Mail Signatures

HTML Signatures

• This was a trick that I originally figured out with the help of Joe Workman.
• the trouble is it’s pretty tricky to get an HTML signature into Apple Mail
  • your need to do the HTML and CSS work
  • Then there is a convoluted process to get it into Mail which doesn’t recognize HTML in the signature editor.
• Joe actually wrote a cool app to handle the tricky parts, called Sigtastic, but it broke with Lion and hasn’t been updated.
  • to be fair the instructions change with each new OS.
• Tips for creating the signature
  • Joe has some nice templates, I actually adapted one of them for mine.
  • Only create the content of the HTML. You won’t have the HTML, HEAD, TITLE, or BODY tags.
  • Stay away from floating divs.
  • Use HTML tables when you need to create more complex structures.
  • Do not try to load external CSS files. Define all CSS inside the HTML.
  • Do not use the style tag to store CSS. Do everything inline using the style attribute in the tag.
  • You cannot use Javascript.
  • Store your images that are used in the signature on a central place online.
    • Dropbox is great for this.
    • I put mine in a folder inside the public folder
    • Then just use Dropbox to copy the link and paste that into the SRC property for the IMG tags.
  • You can also place a vCard with your contact info into Dropbox and link to that in your signature
    • Just create the card in Contacts
    • Drag it out on to the Desktop to create the vCard file.
    • Put that vCard file into Dropbox
    • Right+Click and choose the ‘Share Dropbox Link’ option
    • Here’s a trick. Don’t just use the link you get when you right+click the file on your Mac and choose, “Share Dropbox Link”
      • That link isn’t the link to the file, but a link to a Dropbox page that has the file download link
      • Take the “Share Dropbox Link” and paste that into Safari
      • Then on the page that opens, right+click the ‘Download’ button and choose ‘Copy Link’
      • That is the link you’ll want to use.
      • You can also clean up that link by removing the ‘&token_hash=’ parameter and also changing it to be HTTP, instead of HTTPS
• Once you have the HTML you can open the file in your browser to check it. Now the easy part id over.
• Create a Temporary Signature in Mac Mail
  • Go into Mail > Preferences > Signatures
  • Select the account you want it in and click the ‘+’ to add a new signature
  • Give it a name. You can type something in here, but this is the signature you’ll place your content into, but you won’t be doing that in Mail (that would be too easy)
  • What we’ve just done is create a temporary .mailsignature file.
• Find and open the temp Mail signature file
  • In the Finder open the ‘Go’ menu and choose ‘Go to folder…’
  • Enter: ‘~/Library/Mail/V2/MailData/Signatures’
  • Once in the folder you’ll see a bunch of cryptic filenames. We need to find our one temp signature.
    • The easiest way to find it is to sort by Creation Date.
    • You can use QuickLook to verify you have the right one based on what you wrote in it earlier.
  • Open the file in your favorite HTML editor
    • Mine happens to be Sublime Text 2 currently
    • Other choices include, TextMate, BBEdit, or Coda. Even TextEdit if you’d like.
  • there will be a bunch of metadata in there. Leave that in place
  • copy your HTML signature code and paste it below that meta data replacing everything that is there.
  • save and close the file.
  • back in the finder, select the file you just edited and choose ‘File’ > ‘Get Info’
    • we need to lock the file to prevent Mail from overwriting it.
    • check the ‘Locked’ box in the Get Info window and close it.
• Try out your new HTML signature
  • Open Mail
  • Go to Mail > Preferences > Accounts
  • select the account you originally created the temp signature in
  • now that signature should contain your code.
  • what you will notice is that the images don’t load. They will load when you compose a new message and choose the signature.
    • they only load if you have the
• Adding signatures to iOS
  • Once you have your fancy new email send an email to yourself, but then open it up on your iDevice
  • In Mail on iOS, select the signature and copy it.
  • Now exit Mail and go to Settings > Mail, Contacts, & Calendars
  • Scroll down and tap on Signature
  • Then paste the signature into the box.
  • If you have ‘Per account’ enabled then paste it into the appropriate account.
  • It should retain it’s formatting, etc.

Signed Emails

• Another thing that I do with my emails is I signed them and a lot of people often ask me about that.
• What is an email signature?
  • It’s basically just a file, a certificate, from a certificate authority
  • very similar to an SSL certificate, yet instead of verifying the identity of a web site you’re verifying the identity of someone who sent an email.
• Why would you use one?
  • The main reason would be to verify the person who sent the email is that person
  • A certificate can also be used to verify that an email was not tampered with in transit.
  • You can also use certificate to encrypt your email so that no one else can read it other than the recipient
• Getting a certificate
  • you need to get one from a certificate authority
  • there are many, but Comodo offers them for free.
  • You basically fill out a simple form with your information.
  • You need to provide the email address for the account you want the certificate for
  • You’ll also need to apply for one certificate for each account that you want to get a certificate for.
  • For the key choose, select “2048 (High Grade).
  • Enter a secure “revocation” password.
    • This will be used if your account is ever compromised, say your laptop is stolen.
    • You can use it to revoke the certificate. Then if someone tried to send from your email account the signature not work and will no longer be valid
• Download and Install the Certificate
  • After you complete the registration process you’ll get an email to download the certificate. Just click the link in the email to download certificate to your Mac
  • The file will be a .p7s (certificate) file (could also be a .cer file) and you can just double-click it to install it into your Keychain.
• Using the Certificate
  • Relaunch Apple Mail
  • Now when you compose a new email with an account that has a certificate you should see two new icons in the message bar of the compose window
  • a lock that when pressed will encrypt the message
  • a seal (starburst) that is for signing. Clock this to get a checkmark in the icon meaning the message is signed. If it has an X signing is turned off.
• When you send a signed email the recipient will see a signed security seal letting them know the message was signed.
  • some email clients don’t support S/MIME, so in that case the signature may appear as text at the bottom of the email or as an S/MIME attachment.
• Installing certificates on iOS
  • For the iPhone you’ll need to have a p12 certificate file for the iPhone
  • You’ll get a p12 certificate by concerting your p7s certs that are already installed on your Mac.
    • Applications > Utilities > Keychain Access
    • Select ‘My Certificates’ under ‘Category’
    • Locate and select the certificate you want to use
    • Click File > Export Items…
    • Under the ‘File Format’ drop down choose ’Personal Information Exchange (.p12)
    • Name and save the certificate file
    • Enter a password for the certificate. You’ll need this later to install the cert on the iOS device.
    • Do this for each account you want to use S/MIME certificates for.
  • Email the p12 certificates to yourself
  • Open the email on your target device
  • Click the p12 attachment to install it onto the device
    • You may get a dialog warning that the certificate is unsigned or untrusted. It’s OK. Just tap Install.
    • Enter your device passcode
    • Enter the password for the certificate, click Next to install.
    • Click Done.
    • Repeat this procedure for each certificate/ email account
  • Enable S/MIME and options
    • Settings > Mail, Contacts, & Calendars
    • Choose the Account you want to configure (one you installed a certificate for)
    • Tap the Account name at the top of it’s settings screen
    • Tap Advanced
    • Scroll down to the S/MIME section and turn on S/MIME
      • This will enable you to receive encrypted email
    • Turn ON the Sign option to have iOS Mail sign your email from that account
    • Turn ON Encrypt to have iOS Mail encrypt ALL messages sent from that account.
      • Unfortunately this is a toggle in the Settings and cannot be toggled from the Mail compose screen like on the Mac.
• Send encrypted email
  • To do this your recipient will need to have your public key, and you’ll need theirs to read encrypted email from them.
  • The easiest way to get these with Apple Mail is to simply exchange signed emails
    • Compose a new email in Mail and send it signed to the recipient
    • When they view it your public key will automatically be added to their keychain.
    • They should reply to you with a signed email and then their public key will be added to your keychain.
    • Now you can send each other encrypted email.
    • When you send to their certificated address, you will encrypt the email with their public key by clicking the lock icon in the toolbar of the compose window.
    • When they receive it it will be visible on their Mac or any devices with S/MIME enabled using their private key (certificate).