After entering credentials at the Plesk login page, it loads forever and never logs in. Eventually, it fails with an error:
HTTP Error 500.0 - Internal Server Error C:\Program Files (x86)\Parallels\Plesk\admin\bin\php-cgi.exe - The FastCGI process exited unexpectedly
When attempting to browse the Plesk applications catalog within a subscription, the following error appears:
"APS Catalog error: System error 0xC0000005 occured. Retry"
When attempting to adjust the settings of a mailbox, the following error appears:
Error: System error 0xC0000005 occured.
For Odin Business Automation - Standard (OBA-S):
Any task is pending due to Plesk returning empty results:
Error occurred while deleting domain from Plesk node: Could not connect to Plesk Agent host or response is empty.
When attempting to provision a new hosting plan from OBA-S, the following error appears:
"Error-TEXT: 21:19] [ERROR]  [HSPC::MT::BM::Subscription::PleskDomainSubscription::provision_domain_on_plesk] Error provisioning to Plesk. The following site applications not found on plesk node: joomla, moodle, wordpress, magento, sugarcrm, formmail, typo3, drupal, oscommerce, opencart, zen cart. "
The problem is considered a software issue and is completely fixed in Plesk 12 #MU34.
Make sure that Plesk updated to MU #34, install it if not.