It is not possible to manage mailbox size via Plesk user interface in Web Admin edition.
The only way to manage it is through command-line with administrator privileges.
Examples (both for Linux and Windows):
-
set quota to 100M:
# plesk bin subscription_settings --update example.com -mbox_quota 100M
-
Set the mailbox size to the default value:
Note: default value for subscription is inherited from its service plan
# plesk bin subscription_settings --update example.com -mbox_quota -1
- To change the limit for a specific mailbox, use plesk bin mail utility:
# plesk bin mail --update user@example.com -mbox_quota 50M