4D has been DEP Compliant since 4D v11 SQL Release 4; however, any plug-ins must also be checked to see if they are DEP compliant.
When using the 4D Plug-In SDK it is possible to create a plug-in using the API that is either compatible or incompatible with DEP. There is a setting in Visual Studio which corresponds to the linker flag: /NXCOMPAT
When building a custom plug-in for 4D, it is important to make sure that the linker flag is set appropriately in order for your plug-in to be DEP compliant. If the plug-in depends on other DLLs, then they must be DEP compatible too.
The following image depicts the interaction between 4D and a Custom Plug-Ins:
The image above demonstrates that the linker flag should be checked in both the Open Source API project file, as well as any custom code.
For more information on the linker flag please see: https://msdn.microsoft.com/en-us/library/ms235442(v=vs.80).aspx
For more information on the Plug-in SDK please see: https://sources.4d.com/trac/4d_4dpluginapi