Kaspersky license cannot be retrieved in
Plesk >License Management ->Additional licenses >
KAV.*****.**** > Retrieve Additional Key.
You will get the error:
Status of additional key update The version of your installed software is 12.0, but the current license version is 5.0. Upgrades from 5.0 to 12.0 are not available for this license.
If you try to enable Kaspersky in Tools & Settings > Mail > AntiVirus > AntiVirus Settings and choose Kaspersky AntiVirus.
Error: You have reached the limit on number of mailboxes defined by your Kaspersky license key (1)
The issue is considered to be a software issue and will be fixed in future product updates.
Please use provided id #PPPM-1678 to track maintanance in Plesk 12 release notes.
Subscribe to our knowledge base - each product update comes with corresponding KB article:
Meanwhile you could use following workaround: