In order to allow access to yousendit.com. you need to allow the following URLs and IP addresses in the "To Where" column:
Set the above rule to "Allow". Save and activate your changes and then test. Please note that if domains or IP addresses used by yousendit.com change, then you will need to add those additional resources to your rule in the Cloud.
If you have SSL intercept enabled, you need to disable SSL intercept for 18.104.22.168/22. To do that, please do the following:
1.) Login to the portal (portal.threatpulse.com)
2.) Go to Service > Network > SSL > Pass Through Destination > Pass Through IPs/Subnets (tab) > Add Pass Through IPs/Subne (button).
3.) Enter 22.214.171.124/22 and save.
4.) Click on the Activate button and then test.