SymptomsAfter I applied a manual payment to the invoice from a new customer, all links in the Customer & Business Manager redirect me to the page with the license information and the error:
"You have exceeded the number of customer accounts you can have in the system. Please upgrade your license."
CauseManual payments automatically change customer accounts from the Pending to Active status. This action does not preliminarily check the license limitation, thus allowing you to exceed the active accounts limit.
ResolutionDownload the trial license from Parallels (http://sp.parallels.com/products/plesk/trial/), install it, and deactivate this customer in Customer & Business Manager by changing its status back to Pending. For this, go to the customer's profile, click Edit Details, and select the status in the drop-down list.
Finally, roll your Panel license back.