In our latest build the handling of Shared and Resource mailboxes has been updated and improved. These two resources are now handled via add-ons. We had changed the handling earlier to handle via the service plan but there was issues with resource separation. Resources sold for Shared/Resource Mailboxes would merge with resources of user mailboxes and were problematic and thus we had to change implementation to settle that under the add-ons.
So, if you wish to give your Resellers and End-Customers of Resellers option to create up-to 9999 Shared or Resource mailboxes, you will need to create 2 add-ons. 1 add-on for Resource Mailbox and Other for Shared Mailbox and then sell them via bulk selling section to desired resellers and customers.
Alternatively you can create these add-ons with your desired minimum values and sell different quantities to desired resellers and customers same as other add-ons.
MachPanel 5.5.23 Onwards
Increase Resources for Exisitng subscription (Quota Over Usage):
Navigate through Home » Service Director » General » Reports and click on Quota Over Usage Report.