Error when deleting images within the ASP.Net CKFinder

I'm receiving an error whenever I attempt to delete an image with the Asp.net version of CKFinder 2.3.

Below is the error message

It was not possible to properly load the XML response from the web server.

Raw response from the server: 

Server Error in '/' Application.
Exception of type 'CKFinder.Connector.ConnectorException' was thrown.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. 

Exception Details: CKFinder.Connector.ConnectorException: Exception of type 'CKFinder.Connector.ConnectorException' was thrown.

Source Error: 

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace: 


[ConnectorException: Exception of type 'CKFinder.Connector.ConnectorException' was thrown.]
   CKFinder.Connector.Connector.OnLoad(EventArgs e) in Connector.cs:222
   System.Web.UI.Control.LoadRecursive() +74
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +2207

Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.272

I can create images, rename them, copy them, create folders... but can't delete.

Any thoughts?