Long story short: I attempted to upgrade to 7.5.3. Ended up having to remove ALL psa packages and deleting the database. Installed 7.5.3. Plesk interface works. Web sites work. Webmail website is available for domains. But NO e-mail accounts will login no matter though webmail or a pop3 client. Noticed that the horde database is empty. Reading /tmp/horde.log shows no useful information. Deleting and recreating e-mail accounts through Plesk doesn't work. I am using the same e-mail accounts that I had before the upgrade. I would appreciate any input you could offer to help resolve e-mail logins. It is crucial that I get it up and running soon! Thanks!