Thank you, yes, that was the problem.
But new problem occurred (see below). I think I must change collation, but I don't know on which tables and columns.
(BTW: IMHO, upgrade scripts should run in transaction, now when upgrade process fails, database is in inconsistent state.)
Output:
Upgrading To Version: 0.7.832.0
Installing Membership Provider... - 00:00:00.0156250
Migrating Users... - 00:00:04.1718750
Running Upgrade Script: 0.7.719.0.SqlDataProvider - 00:00:04.3437500
Error!
Error in file:H:\Home\WU_003353_8cc162d90a4e2e0c4de38bba866cf49c\Webs\setupstudio.net\www\bugnet\Install\dbscripts\0.7.719.0.SqlDataProvider.sql
Message:Cannot resolve the collation conflict between "Slovak_CI_AS" and "SQL_Latin1_General_CP1_CI_AS" in the equal to operation.
Running Upgrade Script: 0.7.820.0.SqlDataProvider - 00:00:05.1250000
Error!
Error in file:H:\Home\WU_003353_8cc162d90a4e2e0c4de38bba866cf49c\Webs\setupstudio.net\www\bugnet\Install\dbscripts\0.7.820.0.SqlDataProvider.sql
Message:Cannot find the object "dbo.ProjectRoles" because it does not exist or you do not have permissions.
Running Upgrade Script: 0.7.832.0.SqlDataProvider - 00:00:05.2343750
Upgrade Complete