I got an internal server error while checking out a reserved item to a patron. The plack-error.log showed this error: DBD::mysql::st execute failed: Duplicate entry '4515' for key 'PRIMARY' [for Statement "INSERT INTO `old_reserves` ( `biblionumber`, `borrowernumber`, `branchcode`, `cancellationdate`, `expirationdate`, `found`, `itemnumber`, `itemtype`, `lowestPriority`, `notificationdate`, `priority`, `reminderdate`, `reserve_id`, `reservedate`, `reservenotes`, `suspend`, `suspend_until`, `timestamp`, `waitingdate`) VALUES ( ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ? )" with ParamValues: 0='4095', 1='4310', 2='WLPL', 3=undef, 4=undef, 5='F', 6='4177', 7=undef, 8='0', 9=undef, 10=0, 11=undef, 12='4515', 13='2017-01-26', 14='', 15='0', 16=undef, 17='2017-01-26 14:05:25', 18='2017-01-26'] at /usr/share/perl5/DBIx/Class/Storage/DBI.pm line 1832. DBIx::Class::Storage::DBI::_dbh_execute(): Duplicate entry '4515' for key 'PRIMARY' at /usr/share/koha/lib/Koha/Object.pm line 120 I checked in the old_reserves table and found that there was already an entry with a reserve_id of 4515. Does anyone know how this would happen? I'm running Koha 16.11.20.000 on Debian 8 and just updated from packages last Wednesday if that's any help. -- Tim McMahon Technical Services West Liberty Public Library