You are running Symantec Encryption products on a version of Windows that has reached the end of Microsoft support.
You wish to know whether Symantec Encryption products are still supported on such versions.
For example, support for Windows 7 ended on January 14, 2020 as did support for Windows Server 2008 and 2008 R2.
No Encryption products are supported if they are running on versions of Windows that are out of Microsoft support.
This includes products that were supported on that version of Windows at the time of their release. For example, even though Endpoint Encryption release 11.3.0 was supported on Windows 7 SP1 at the time of its release, that support ended on January 14, 2020. Likewise, Encryption Desktop release 10.4.2 MP4 was supported on Windows 7 SP1 at the time of its release, but that support also ended on January 14, 2020.
Therefore please upgrade to a version of Windows that Microsoft supports and use a version of the Encryption product that supports that version of Windows.