The Symantec Management Agent seems to install and all the files are there but the service will not start.
 10/23/2013 9:21:02 AM (AeXNSAgent.exe) Agent
Failed to initialize agent storage: File not found
One of the following:
Scenario 1) Agent not fully installed
Scenario 2) Permissions have been changed on the 'MachineKeys' or 'S-1-5-18' folders under 'C:\ProgramData\Microsoft\Crypto\RSA'
Scenario 1) Reinstall the agent on the system having this issue
Scenario 2) By default Everyone should have special permissions on the 'MachineKeys' folder and System Account should have read/write on the S-1-5-18 folder.