For a fix to the issue “Avasrt UI failed to load error”, on the keyboard press win+R this will start the windows services console then in the field enter “services.msc then click “ok” then in the services console search and right click “Remote desktop services” and then select “properties” then in the “general tab” click on the drop down menu further select “automatic” after that “click “Apply” to confirm changes after that get your system restarted and try to open Avast antivirus again and if you still need more help or support then ask help from the experts at Avast helpline number & http://www.avast-phone-number.com/ & http://www.avast-phone-number.com/blog.html