Mac OS X has a reputation for being user friendly, and in almost every single way it is. Unless you want to have a fancy HTML email signature and are using Apple Mail that is. For some bizarre reason using an HTML signature is a shockingly difficult proposition.
Thankfully, after creating my own HTML signature, and installing a handful for clients, I’ve figured out a simple way to get the job done. These instructions apply to Mac OS X 10.12 (Sierra) but they should also work for older versions of Mac OS X as well.
These instructions were inspired by Matt Coneybeare’s awesome instructions, but I’ve take a little different route that is much simpler. If my simplified instructions don’t work for you I highly recommend giving Matt’s more detailed instructions a try. He has specific instructions for Lion, Mountain Lion, Mavericks or Yosemite, El Capitan as well.
- In Apple Mail we need to create a new placeholder signature that we will be replacing with our new, fancy HTML signature. Go to Preferences > Signatures and click on the + icon to create a new signature. Insert placeholder text, this is only needed to ensure you are editing the right signature file in a later step.
- Ensure that the new signature is associated with the email account you want to use it with by dragging it’s name from the middle colour to the email account in the account list on the left. You can also highlight the email account you want to use and then select the new placeholder signature from the Choose Signature menu at the bottom of the window.
- Close the Preferences window and quite Apple Mail.
- Now you need to create an HTML signature. You can write your own HTML code if you know the ins and outs of HTML email signatures. The HTML should not include a HTML or head tag and should only use inline CSS and basic HTML elements.
If you need a bit of help, the HubSpot Email Signature Template Generator is free, easy to use and produces nice looking email signatures. - Now we have to find the placeholder email signature you created in step 1. Because Mac OS X now hides all system files by default, you have to know EXACTLY where to look. In the Finder > Go > Go To Folder (⌘ + Shift +G) and paste the file path shown below into the window that opens.
~/Library/Mail/V4/MailData/Signatures/
- Hit Go and you will be taken to a folder contains all of your email signatures. The easiest way to find your placeholder email signature is to click on the Date Modified column title and select the newest file with a .mailsignature file extension.
- Open this mail signature file using TextEdit by dragging the file onto TextEdit in the dock, or by right clicking on the file and using the Open With command. Ensure you have the right signature by finding the placeholder text you inserted in step 1.
- Paste your new HTML email signature below the Mime-Version: line, ensuring you keep the 5 lines of metadata and replace everything else with your new signature. Save the file and close it.
Even though you’ve saved your new signature it’s still possible for Mail to revert to the original version and overwrite your new signature. Select the HTML signature that you just edited in step 8, select Get Info (⌘I) and select the Locked checkbox.- And that’s it. To test that your new signature is working correctly just compose a new email.
Hopefully these simplified instructions worked for you. If not I highly recommend trying the full instructions by Matt Coneybeare’s. He has specific instructions for Lion, Mountain Lion, Mavericks or Yosemite, El Capitan as well.
