The new connections to the ASA firewall fail, and the ASA produces crypto accelerator errors. When this issue occurs, the IPSEC ERROR: Asynchronous operation failed syslog error message appears.
This issue appears due to the presence of Cisco bug ID CSCsd43563.
This issue is first identified in ASA version 7.1(1.2).
For a temporary workaround:
Issue the reload command in the ASA in order to fix this issue.
In order to completely resolve this issue:
Upgrade the ASA version to 7.1.( 2.43 ) or later. In order to download the latest software, go to Cisco Downloads.