Installing an HTML signature in Snow Leopard and Lion
Go to Mail's preferences
Go to the Signatures tab, and create a new signature by clicking the + button.
Quit Mail (Cmd-Q), open Finder, and go to your Library folder
Go to Mail/V2/MailData/Signatures
Sort your signatures by date, and identify the "youngest" one
Copy the name of the youngest .webarchive signature file
Change the name of your HTML .webarchive file. If your signature is in a .HTML file, open it with Safari and save it as a WebArchive
Copy paste your .webarchive file into your Signatures folder in the Library
You're done! Congratulations, you have successfully installed a new HTML signature!
Installing your HTML signature in Snow Leopard and Lion is a quick 9 step process, and if you know what you’re doing, it can be done in under a minute. If you follow these step by step instructions carefully, you’ll have your HTML Signature in no time.
As a word of caution, you need your HTML Signature to be in a .webarchive file. If your HTML signature is in a .HTML file, open it with Safari and save it as a WebArchive by going to File/Save As.
From Mail, go to Preferences / Signature
Create a new signature for your account by clicking on the + sign. This will create an automated signature
Quit Mail. Simply closing the window is not enough, so be sure you Quit the program. Open Finder, and go to your Library. If you click on the Go tab, you will reveal the Library by holding the “option” key on your keyboard down
Go to Library/Mail/V2/MailData/Signatures/
Sort the signature files by Date, and copy the name of the youngest file. In Lion and Snowleopard, these are the files that end with .webarchive
Change the name of your HTML Signature file by pasting the name of the file in Signatures/
Copy/Paste your signature file (or drag) into the Signatures folder. When they ask you if you want to Replace the file, replace it. If they do not ask you, then you are either not copying a .webarchive file, or you did not copy the file name properly.
Open Mail, and that’s it, your signature is installed