Thanks for the help. The koha-upgrade-schema step went well until this: Upgrade to 3.19.00.037 done (Bug 13810: Change collate for tagsubfield (utf8_bin)) {UNKNOWN}: DBI Exception: DBD::mysql::db do failed: Incorrect datetime value: '0000-00-00 00:00:00' for column `koha_cfl`.`virtualshelves`.`created_on` at row 1 at /usr/share/perl5/DBIx/Class/Schema.pm line 1118. DBIx::Class::Schema::throw_exception(Koha::Schema=HASH(0x55f9a91d9528), "DBI Exception: DBD::mysql::db do failed: Incorrect datetime v"...) called at /usr/share/perl5/DBIx/Class/Storage.pm line 113 DBIx::Class::Storage::throw_exception(DBIx::Class::Storage::DBI::mysql=HASH(0x55f9ae477430), "DBI Exception: DBD::mysql::db do failed: Incorrect datetime v"...) called at /usr/share/perl5/DBIx/Class/Storage/DBI.pm line 1501 DBIx::Class::Storage::DBI::__ANON__("DBD::mysql::db do failed: Incorrect datetime value: '0000-00-"..., DBI::db=HASH(0x55f9ae93d640), undef) called at /usr/share/koha/intranet/cgi-bin/installer/data/mysql/updatedatabase.pl line 10391 Here are the relevant lines from updatedatabase.pl: $DBversion = "3.19.00.038"; if ( CheckVersion($DBversion) ) { $dbh->do(q| ALTER TABLE virtualshelves ADD COLUMN created_on DATETIME NOT NULL AFTER lastmodified |); I tried running this ALTER statement manually, and it succeeded. So the problem does not seem to be MariaDB. -- If you're careful enough, nothing bad or good will ever happen to you. --Ashleigh Brilliant