CentOS 5 will not be updated after March 31, 2017 (see the CentOS FAQ). In consideration of the End of Life of CentOS 5, you should plan your update to IDACT 2.1, which is based on CentOS 6. Contact email@example.com for assistance.
To quickly check, log in to your Enforce or a Detection server (not the appliance itself) and run:
If the output indicates CentOS 5 then Symantec DLP 14.5 or better will not run.