Users Receive an Error Message After Opening PDF Attachments

If your users are receiving a Security Block error message (see below) when opening PDF attachments from a phishing campaign, you can edit your settings in Adobe Reader, Acrobat, or Document Cloud to whitelist KnowBe4 and allow that connection to occur.

Example of the error message:

To make sure users do not receive this error message, you can configure Adobe to automatically trust sites from my Win OS Security Zones (which is enabled by default) and then add KnowBe4's domains to the Windows Trusted Sites via Group Policy. 

First, make sure Adobe is configured to automatically trust sites from my Win OS Security Zones. The settings are located under Edit --> Preferences --> Security (Enhanced) --> Privileged Locations --> "Automatically trust sites from my Win OS security zones".

Second, you will need to submit a support ticket and request a list of our phish domains. Add those phish domains, in addition to the KnowBe4 hostnames below, to the Windows Trusted Sites (can be done via Group Policy):

• knowbe4.com
• phishtest.knowbe4.com

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