Thanks in advance!
Best answer by ProTruckDriver
Happy Holidays. I'm sorry you're having trouble installing WSA on your new Mac. Mojave has a lot of new security features then previous versions. Apple may have done a silent security update that is stopping the install. The best I can recommend is putting in a Support Ticket or calling Webroot.
Please submit a Support Ticket or Contact Webroot Support to sort this problem. This service is FREE with a Paid Subscription.
Support Ticket System is Open 24/7
Note: When submitting a Support Ticket, Please wait for a response from Support. Putting in another Support Ticket on this problem before Support responses will put your first Support Ticket at the end of the queue.