Where to store custom DLLs
To deploy your custom DLLs on a Sage CRM server, copy them to
{Sage CRM installation folder}\CustomDotNet
By default, Sage CRM is installed to %ProgramFiles(x86)%\Sage\CRM\CRM.
You can copy your .NET .dll file to the CustomDotNet folder manually or specify that folder as the build location in the Microsoft Visual Studio project properties. The CustomDotNet folder contains the RelatedEntities.dll file. Do not move, delete, or rename this file, as the Relationships feature of Sage CRM depends on this DLL.