Parallels Plesk Panel 11.5 is registered in PBA-S 4.5.
Task "Plesk Domain DNS synchronization" has status "Error" at
Top > Configuration Director > Logging and Errors > Action Log > Tasks Queue.
The following notification is shown in DEBUG PBA-S log:
[2013/12/31 11:25:56] [DEBUG]  [HSPC::MT::Plesk::PleskGate::__send_request_to_agent] REPLY_DATA=<?xml version="1.0" encoding="UTF-8"?><packet version="22.214.171.124"><dns><get><result><status>error</status><errcode>1026</errcode><errtext>DNS service is not enabled</errtext></result></get></dns></packet>
BIND DNS Server is not installed or disabled in Parallels Plesk Panel 11.5.
Note: Plesk DNS is master for PBA-S DNS. If DNS service is disabled in Plesk (master DNS), DNS zone becomes disabled in PBA-S (slave DNS).
Install component BIND DNS Server through Plesk GUI Autoinstaller:
Login to Parallels Plesk Panel as admin > Tools & Settings > Updates and Upgrades > Add/Remove Components
BIND DNS Server
Remember to enable the component if it's already installed:
Plesk Admin > Tools & Settings > Server Components > BIND DNS Server