Before We Begin

Create a Safe Environment for Postbox

Virus Checkers and Internet Security Programs can cause major issues with desktop email applications. These programs can block ports, quarantine and/or lock mail or preferences files, or even prevent Postbox from loading. Most issues that customers experience with Postbox can be traced back to these applications.

Before getting starting with Postbox, please ensure that these programs are set up in ways that will allow Postbox to function normally. This includes keeping email ports such as 143, 993, 995, 465, 587, and 25 open, and ensuring that Postbox mail and preferences files are not locked or altered. Please refer to the operating manuals for your security package for instructions on how to configure the package for use with a desktop email client.

Ensure that your Mail Server is Configured for IMAP/POP/SMTP

If your server is set up to use IMAP/POP/SMTP, and if your settings are entered correctly, then Postbox will connect. We guarantee it!

Contact your ISP, email hosting company, or IT manager to ensure that your email server(s) are configured to use IMAP, POP, and SMTP. If you are administering your own account, such as Gmail account, then perform a Google search on the web for instructions on how to configure the account for IMAP, for example, search for "Gmail IMAP" or "Office 365 IMAP".

Know Your Account Settings

Postbox works with any IMAP or POP server. If your email server supports POP/IMAP/SMTP, and if the correct settings are entered into Postbox, it will connect. We guarantee it!


While Postbox's Account Wizard can assist you with account configuration, we recommend that you check with your ISP, email hosting company, or IT manager on the best settings to use. There are several ways to accomplish this:

  1. Log into your email account on using a web browser, and look for the configuration settings within your account profile. 
  2. Perform a Google search on the web, such as "Office 365 IMAP settings" or "Yahoo IMAP settings." 
  3. Request the settings directly from your ISP, email hosting company, or IT manager, as they will have this information readily available for you. Here's a template that you can use to request account settings:

Incoming Server

  • Account Type (POP or IMAP):
  • Server name or address:
  • Port:
  • User Name:
  • Connection Security (SSL/TLS, STARTTLS, etc.):
  • Authentication (Password, OAuth2, etc.):

Outgoing Server

  • Server name or address:
  • Port:
  • User Name:
  • Connection Security (SSL/TLS, STARTTLS, etc.):
  • Authentication (Password, OAuth2, etc.):

Enjoy the Ride!

Postbox is an incredibly deep application, and if we described everything, we would never get to the end of this guide. Once you start using Postbox, please take the time to browse through its Preferences/Options to see what's available.