[otrs] Notifications about new messages but don't see them

I have migrated OTRS to a new server today. I rsync'ed /opt/otrs and ran SetPermissions.pl Everything works fine, but new articles do not appear until I add a new article. Customer A has an active ticket. Customer A replies. I get a notification email and see the star in the OTRS backend. However, when I click the ticket and get an overview of all the articles, the new article does not appear. When I add a new article, such as a note, the new articles appear as unread. Help? Met vriendelijke groet, with kind regards, William Edwards Cyberfusion - Hosting voor webbureaus en bedrijfskritische applicaties W. https://www.cyberfusion.nl/ E. wedwards@cyberfusion.nl T. 040 - 711 44 96