UriFormatException in a VMware workstation on Windows 8 (4270749)

Running Toad for SQL Server on Windows 8 in VMware workstation 9.0.1 occurs after a few minutes of use.

Disabled check for updates and do not open the web page at startup is enabled.

VMware connected in NAT mode and Internet is connected through an authenticated proxy server

********************************************************************** Exception Information ********************************************************************** Exception: System.UriFormatException Message : Invalid URI: Invalid port specified. Stack Trace: at System.Uri.CreateThis(String uri, Boolean dontEscape, UriKind uriKind) at System.Uri..ctor(String uriString) at Quest.Toad.Util.Internet.ToadWebProxy.GetProxy(Uri destination) at System.Net.ServicePointManager.FindServicePoint(Uri address, IWebProxy proxy, ProxyChain& chain, HttpAbortDelegate& abortDelegate, Int32& abortState) at System.Net.HttpWebRequest.FindServicePoint(Boolean forceFind) at System.Net.HttpWebRequest.get_ServicePoint() at System.Net.AuthenticationState.PrepareState(HttpWebRequest httpWebRequest) at System.Net.AuthenticationState.ClearSession(HttpWebRequest httpWebRequest) at System.Net.HttpWebRequest.ClearAuthenticatedConnectionResources() at System.Net.HttpWebRequest.Abort(Exception exception, Int32 abortState) at System.Net.HttpWebRequest.AbortWrapper(Object context) at System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem() at System.Threading.ThreadPoolWorkQueue.Dispatch() at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback() **********************************************************************