You need to follow this document sot hat you can set the access time to not modified
Incremental backup jobs create a full backup after Symantec Endpoint Protection runs a scan
http://service1.symantec.com/SUPPORT/ent-security.nsf/docid/2007101816043548
Solution:
The following setting suppresses file modifications for attribute updates, last access dates, and security descriptors.
- To fix the problem on 32-bit versions of Symantec Endpoint Protection client, create the following DWORD value and set it to 1:
HKEY_LOCAL_MACHINE\SOFTWARE\Symantec\Symantec Endpoint Protection\AV\NoFileMod
- To fix the problem on 64-bit versions of Symantec Endpoint Protection client, create the following DWORD value and set it to 1:
HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Symantec\Symantec Endpoint Protection\AV\NoFileMod
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