UEFI and Secure Boot compatible PCs/Operating Systems prevents Data Control from working
Please increase development effort on the re-engineering of DLP so it does not use the AppInit_DLLs and therefore can have Secure Boot enabled.
Microsoft post in May 2018:
The AppInitDLLs mechanism is not a recommended approach for legitimate applications because it can lead to system deadlocks and performance problems.
The AppInitDLLs mechanism is disabled by default when secure boot is enabled.
Using AppInit_DLLs in a Windows 8 desktop app is a Windows desktop app certification failure.
Matt Torley commented
The first Sophos KB article about this is from 2014!
That means Sophos has gone for almost 6 years without getting their DLL's signed or figuring something else out.