- Download the Add-on to your computer, such as the Desktop.
- In Postbox, go to the Tools menu and select Add-ons.
- Click the Gear icon or button in the upper right corner, then select Install Add-on From File...
- Browse to the location of the add-on and select it.
- Restart Postbox.
Trouble-Shooting and Support
Add-ons can change the DNA of Postbox in ways that are incompatible with its default behavior. If Postbox is not operating the way you expect, then temporarily disable add-ons to see if the problem clears up for you.
Postbox does not support the functionality of 3rd party add-ons, as it is up to each developer to support the functionality of the add-ons they author. If an add-on is not working correctly, please contact the add-on developer directly.
Postbox 5 Add-ons
|macOS Sharing 1.0.2||Postbox, Inc.||Allows content to be sent through Postbox using the macOS Share menu.||Download | Instructions|
|70 Email Templates Every Business Needs 1.0||Postbox, Inc.||70 professionally written email responses that anyone can customize and use. You'll receive emails for finding a job, hiring, making introductions, reaching out to investors, sales, and more.||Download | Instructions|
|25 Beautifully Designed Email Signatures 1.0||Postbox, Inc.||25 professionally designed email signatures that will present you in the best light possible. Each signature is fully customizable, and contains all the code examples you need to make a lasting impression.||Download | Instructions|
|Cloud File Sharing Add-on 1.1.1||Postbox, Inc.||Share links to your Dropbox, Box, and OneDrive files instead of mailing the files themselves. Only available for Postbox 4 and 5.||Download | Instructions|
|Vacuum Postbox 1.1||Postbox, Inc.||Adds a "Tools | Indexing | Vacuum..." menu item which allows you to vacuum your Postbox index to reclaim disk space and improve performance.||Download|
3rd Party Add-ons
These add-ons are not developed or supported by Postbox, Inc.
|Markdown Here||Adam Pritchard||Markdown Here allows you to write complex email in simple text, never taking your hands off the keyboard.||Download|
|SpamSieve||C-Command Software||Integrate Postbox with SpamSieve's powerful junk filtering on macOS (requires download and purchase of SpamSieve from C-Command Software).||Download for macOS|
|ImportExportTools||kaosmos||Import and Export Messages.||Download|
|Enigmail 1.2||The Enigmail Team||Send and receive signed and encrypted messages using OpenPGP provided by GnuPG. You also need to install GnuPG.||macOS | Windows|
|MinimizeToTray Revived||Nils Maier||Minimizes Postbox to the system tray on Windows.||Download|
|MailHops||Andrew Van Tassel||MailHops maps the route an email took to get to you.||Download|
|QuickFolders||Axel Grude, Alexander Malfait||Turn your favorites into tabs - open folders and subfolders, move mails without scrolling around or searching.||Download|
|SmartTemplate4 v1.4||Axel Grude, Marky Mark||SmartTemplate4 offers an easy way to automatically create customized replies by auto-inserting various mail headers.||Download|
|Zombie Keys||Axel Grude, Kai Bolay||This extension implements Microsoft's Keyboard shortcuts for international characters.||Download|