Scans fail and your logs contain Decomposer 21 errors similar to the following log entry:
Date = Fri May 21 13:07:44 EDT 2021
Event = The Symantec Protection Engine has encountered a scan error
Event Severity Level = Error
Scanner = Decomposer
Result ID = 21
File name = file.zip
Client IP = 192.0.2.3
Scan Duration (sec) = 0.083
Connect Duration (sec) = 0.126
Symantec Protection Engine IP address = 192.0.2.2
Symantec Protection Engine Port number = 1344
Uptime (in seconds) = 117
Date/time of event(with millisec) = 1621616864823
Symantec Protection Engine Host Name = computer.domain
Process ID = 23653
This error indicates a problem was encountered extracting the contents of the container.
Specific causes for this error vary. For more specific information, enable CSAPI debug logging, reproduce the error, and then create a technical support case for assistance troubleshooting.
Enabling CSAPI Debug Logging on Windows:
https://knowledge.broadcom.com/external/article/157519/
Enabling CSAPI Debug Logging on Linux:
https://knowledge.broadcom.com/external/article/164895/
As previously stated, while specific cases for this error may vary, it may be possible that re-packing the original file contents again into a new container file will correct the problem.