When i tried to upgrade to Avast pro it showing white screen on checkout. I repeated the checkout procedure.
But no change…
Hi nullchar, welcome to the forum 
Have you updated to the latest version first ? https://forum.avast.com/index.php?topic=176600.0
I am not sure if this is ( related to ) your problem, but in previous version(s) there were issues with payment gates.
Greetz, Red,.
Hi Red This not a issue of avast! store .My upgrade screen not show white screen.Pls try to repair avast! and pls check your net connection.I am successfully upgraded to AIS2015 in my laptop.But i like avast! free antivirus more so i stick with avast! free on my Pc.
Repaired, updated virus def & program but no change 