Business users: Perform these steps in ESMC
Press the F5 key to open Advanced Setup.
Click Web and Email → Web access protection.
Expand URL Address Management and then click Edit next to Address list.
Select List of addresses excluded from content scan and then click Edit.
Click Add in the Edit list window.
Type the website or domain you want to exclude in the Enter a mask that specifies a URL address field and click OK.
When you are finished excluding websites, click OK to save your changes and exit the Advanced setup window.