Async operations with 2.0 framework

Question

We have been running our application successfully for over a year using async calls. We recently upgraded to .net 2.0 framework on our test server and our async calls are having some issues. All DB calls are done asynchronously, here is the pattern we use: private void somefunctioncall() { try { ProssessServerCall pas = new ProcessServerCall(); AsyncCallback RemoteCallback = new AsyncCallback(this.callbackfunction); ValidateDataDelegate del = new ValidateDataDelegate(pas.ValidateData); IAsyncResult ar = del.BeginInvoke(some parameters); SetWait(); //this } catch(Exception e) { ..... } } private void callbackfunction(IAsyncResult ar) { try { ValidateDataDelegate del = (ValidateDataDelegate)((AsyncResult)ar).AsyncDelegate; dataset ds = del.EndInvoke(ar); NoParmDelegate ed = new NoParmDelegate(this.BackToUIfunction); this.Invoke(ed); } catch(Exception e) { CallBackMessage(e.message,true); } ResetWait(); //were thinking this caused the problem } //Callback message Protected void CallBackMessage(string message,bool showstaff) { CallBackMessageDelegate ed = new CallBackMessageDelegate(this.ShowCallBAckMessage); this.Invoke(ed,new object[](message,showstaff}); } } protected void ResetWait() { try { NoPartDelegate ad = new NoParmDelegate(this.ResetCursor); this.Invoke(ad); } catch(Exception ex) { } } I think maybe the ResetWait is causing the problem, what happens is that we appear to be in a loop. The callbackfunction keeps getting called again, so the endinvoke gets called again, which causes an InvalidOperationException to be thrown, cause you can't call EndInvoke more than once from asynch call. We did change the ResetWait function to: if(this.InvokeRequired) { noparmdelegate ad = new noparmdelegate(this.resetcursor); Invoke(ad); } else ResetCursor(); } This seemed to work, but then folks were still having some issues. We are stumped, any ideas anyone. Do we need the InvokeRequired on all Invoke calls in the callback function? Katie