This article provides resolutions to some common extension errors. 

My extension is compiling fine, but I can't launch the application from Visual Studio.

Error message from log file

Unable to load required module C:\Users\.....\SystemWeaver\Client\swExplorerExtensions\Systemite.SystemWeaver.Explorer.dll.

Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information.


One cause for this error is the usage of the wrong version of the SystemWeaverExtensionsAPI. Confirm that you are using the correct version.

My extension will not load.

Error message from log file

Error loading module: Unable to instantiate managed plugin class "SWExtension.XXXXX". Most likely the type is not declared as "public", type or assembly are marked as ComVisible(false), or missing/incorrect license file is detected.


One cause for this error is the usage of the wrong version of RemObjects Hydra. All extensions for the SystemWeaver client must use version See Prerequisites.

When I leave an extension view, I am getting a "Error clearing extension" error.

Example error 



Contact the maintainer of the extension. For extension views, the method: IswItemViewContent.SetCurrentItem 

that you implement on the item view content is now called with item == null when the view goes out of scope. Ensure that you check for this and clear the control, removing all references to any SystemWeaver API interfaces. If this is not done, the following message will now display when a user moves away from the view, if the item view content is not cleared properly. This is a breaking change.