Hi, I'm a newbie to Koha, and am experiencing a page load error for a newly migrated library site. On successful login to the staff (-intra) site it persistently results with: /Software error: output_pref is called with 'dateonly' (ref SCALAR), not a DateTime object For help ... / Some background, the migration is from a functioning Koha site on version 3.20.03.00 going to package based version 17.05.04.000 on a Debian 9.2 VM. I also attempted a migration to the oldest stable package v.16.05.17.000, however, received a software error: / "Can't locate object method "ymd" via package "dateonly" (perhaps you forgot to load "dateonly"?)"/ Nothing untoward was noted during the schema update of the imported DB (I can post output if desired). The OPAC site for the migrated DB is working fine. Also, I've created a new blank test library instance which works fine for both staff and OPAC vhosts on the new VM. Perl v.5.024001 (and the required modules) are reported as OK. MySQL mysql Ver 15.1 Distrib 10.1.26-MariaDB, for debian-linux-gnu (x86_64) using readline 5.2 Apache version: Server version: Apache/2.4.25 (Debian) Any assistance resolving this is appreciated. JohnC -- Sent from: http://koha.1045719.n5.nabble.com/Koha-general-f3047918.html