 | Important: Some security programs prompt you to restart your computer to allow the changes to take effect. |
If your contacts are telling you that they're receiving your email but content isn't displaying properly, a good place to start is to have them check the settings in their email client and their web browser to make sure that their settings enable images to display.
If those actions don't help, the next step is to check their security program, which is any filtering system they have in place to protect malicious content from reaching them, like Office365 or Microsoft Defender, or it can be their mailbox setup. Firewall and intrusion prevention security programs can block URLs or IP addresses, which can prevent images from showing in your emails or prevent the web version of your email from displaying. Your contacts may need to talk to their mail admin or IT person to discuss what's causing the URLs to be blocked.
Your contact can tell a security program that content from Constant Contact is okay to view by putting Constant Contact's domains or IP addresses on a safelist (formerly referred to as a whitelist):
If the program allows website URLs, have your contact copy the following Constant Contact URLs and add them to their safelist:
 | Did you know? The URLs you added as text links, button links, or clickable image links in your email while you were creating it can also cause your email to be blocked by a security program. If you've added all the URLs in the above list to a safelist and are still being blocked, it's a good next step to check your own content for something that triggered your email to be blocked. |
If the program allows IP addresses, have your contact add these Constant Contact IP Ranges to their safelist:
The formatting (CIDR notation) above signifies a range of IP addresses which is equivalent to 208.75.123.* and 205.207.106.*
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