When attempting to install Symantec Endpoint Protection 12.1 on non-core Windows Servers, the installation fails with the error message: "Symantec Endpoint Protection cannot be installed without 32-bit application support." This occurs even though 32-bit application support is enabled.
Windows installer logs will contain an error similar to the following:
MSI (c) (D4:7C) [11:34:57:410]: Product: Symantec Endpoint Protection -- Symantec Endpoint Protection cannot be installed without 32-bit application support
Action ended 11:34:57: No32BitSupportError. Return value 3.
This issue may have multiple causes. One possible cause is that the system is missing a critical security patch for the Windows Installer, MS15-074.
Customers have reported that installing the patch for this Windows Installer Vulnerability resolves the issue in some cases. For instructions on how to acquire and install this patch, please refer to the following Microsoft Article: https://support.microsoft.com/en-us/kb/3072630