Resolution
Log into mysql with admin privileges:# mysql -uadmin -p`cat /etc/psa/.psa.shadow` and run the command
USE psa;
CREATE TABLE `exp_event` (
`source` enum('pa','plesk') default NULL, `event_type`enum('started','stopped','created','updated','deleted','status_changed','terminated','flushed','installed','uninstalled','siteapp_added','siteapp_removed','expired') NOT NULL default 'started',
`event_time` datetime NOT NULL default '0000-00-00 00:00:00',
`obj_class` enum('license','service','ip_address','admin_info','siteapp','client','client_limits','client_status','client_prefs','client_perms','client_ip_pool','domain','domain_limits','domain_user','domain_status','phosting','fhosting','subdomain','mailname','webuser','maillist','dns_zone','mailname_antivirus','mailname_spamfilter','mailname_mailgroup','mailname_autoresponder','mailname_attachment') NOT NULL default 'license',
`obj_id` varchar(255) default NULL,
KEY `source` (`source`,`event_type`),
KEY `source_2` (`source`,`event_type`,`obj_class`),
KEY `source_3` (`source`,`event_time`,`event_type`,`obj_class`)
) TYPE=MyISAM;
QUIT;