Problem:

You want to load a (Premium) DraftSight addin created on another system or with your own system in the past.

However, the system might be updated ever since, i.e., the MS .NET framework or the DraftSight release.

When loading the new addin (By using DraftSight File menu -> Open -> browsing to the add-in.DLL),

the DraftSight Command prompt replies with a message saying that the addin dll is not a valid add-in.

Solution:

Register the addin to your Windows system. For example, if the system is .NET 4 framework of 64 bit:

1)      Open a Windows Command Prompt

2)      Change directory to folder C:\\Windows\\Microsoft.NET\\Framework64\\v4.0.30319 (or the .NET current version)

3)      Type this command with those options:  

               regasm /codebase /tlb ".DLL" 

4)      If the addin DLL was registered successfully, the Windows Command will return this message:

 ...

Types registered successfully

Assembly exported to 'C:\\\\.tlb', and the type library was registered successfully

...

5)      Load the addin in DraftSight.

Tips:

Make sure to register the Release version (not the Debug)  add-in DLL. It may be required to run the Windows Command Prompt as an administrator.

That’s done by right- mouse click on the Command Prompts icon and selecting “Run as an administrator”.