Symptoms

When attempting to load the K2 Designer, it errors with:

Could not load file or assembly 'SourceCode.Forms.Management, Version=4.0.0.0, Culture=neutral, PublicKeyToken=16a2c5aaaa1b130d' or one of its dependencies. Either a required impersonation level was not provided, or the provided impersonation level is invalid. (Exception from HRESULT: 0x80070542)

at SourceCode.Hosting.Client.BaseAPI.BaseAPIConnection.RemoteCall(String TypeName, String MethodName, Objectt] Parameters, Booleann] NullList, MarshalMessageType CallType)
at SourceCode.Hosting.Client.BaseAPI.BaseAPI.RemoteSessionCall(String TypeName, String MethodName, Objectt] Parameters, Booleann] NullList)
at SourceCode.Forms.Management.FormsManager.DoSessionCall(String method, Objectt] parameters, Booleann] nullList)
at SourceCode.Forms.Management.FormsManager.GetControlTypesInternal()
at SourceCode.Forms.Management.FormsManager.GetControlTypes()
at SourceCode.Forms.Controls.Web.SDK.Utilities.ControlsAjaxModule.Initialize()
at SourceCode.Forms.AppFramework.BundlingModule.PostAuthenticateRequest(Object sender, EventArgs e)
at System.Web.HttpApplication.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Booleanandamp completedSynchronously)

 

Diagnoses

This error indicates perhaps a files permission issue.
 

Resolution

Granting the K2 Service Account Local Administrator on the K2 Server resolved the error.

If needed, more granular permission can be applied as per:
http://help.k2.com/onlinehelp/k2blackpearl/icg/4.7/default.htm#Plan/Required_Permissions.htm