same here, stuck at 55% then 71% and never ends, try to add to the hosts files another ip address server for s15.upd.kaspersky.com, the ip address of S13 or S12, but nothing changes the behavior of going after s15.upd.kaspersky.com. seems the server (s15) has issues with the sync, too many errors of validating signature of file x or y . and it’s impossible to setup the mirror server i want to use, don’t know why.