SymptomsParallels Plesk Panel is assigned to Centralized Mail through Parallels Plesk Expand. Mail service is managed on Centralized Mail server and remote mail accounts are accessible through the Remote Mail button:
Domains -> DOMAIN.TLD -> Mail -> MAIL@DOMAIN.TLD -> Remote Mail
However local mail account is opened when click mail shortcuts on the Desktop page. If new mail account is created on local mail server this causes synchronization problem in Parallels Plesk Expand.
ResolutionMail shortcuts are not changed when Parallels Plesk Panel is assigned to Centralized Mail server. They still direct to the local server.
To avoid synchronization problems in Parallels Plesk Expand you should access mail accounts through the Remote Mail link only.
Disable the mail accounts shortcuts in the interface of Parallels Plesk Panel:
Server -> Interface Management -> Desktop Presets
Click the desktop preset you want to reconfigure and uncheck Mail accounts tab under the Favorites title.