Hello,
I am sure, the Symantec Endpoint Protection 11.0.5002 32 bit package could not be installed on 64 bit machine??
I would suggest you to Migrate to the Latest Version of Symantec Endpoint Protection version 11.0.7101 and go with AutoUpgrade Feature, where in you can Migrate all the clients to the Latest version without any issues.
Migrating to Symantec Endpoint Protection 11.0.7101 (RU7 MP1)
http://www.symantec.com/docs/TECH171552
Upgrading clients by using AutoUpgrade
http://www.symantec.com/docs/TECH96789
Again, I agree with Beppe.
Symantec Endpoint Protection 11.0 Release Update 5 (RU5) or higher is supported on Windows 7 and Windows Server 2008 R2. However,
Symantec Endpoint Protection 11.0 Release Update 7 (RU7) and Symantec Endpoint Protection 12.1 or higher is supported on Windows 7 SP1 and Windows Server 2008 R2 SP2.
Check this Article:
https://www-secure.symantec.com/connect/forums/windows-72008-r2-sp1
I would request you to Migrate to the Latest Version of Symantec Endpoint Protection ie; Symantec Endpoint Protection 11.0.7000 and then to Symantec Endpoint Protection 11.0.7101
Hope that Helps!!