web.Folders[].Files.Add crashing with no error

Hi.

In the following code my intention is to upload a file programmatically from a folder on disk to a SharePoint 2010 document library. 

// Get the destination libraries                                    
                                    SPList destination = web.GetList(web.ServerRelativeUrl + sDocLib);
                                    // Get the root folder of the destination we'll use this to add the files
                                    SPFolder folder = web.GetFolder(destination.RootFolder.Url);
                                    web.AllowUnsafeUpdates = true;//SPFile curFile = web.Folders[sDocLib].Files.Add(sSourceFile, content);SPFile curFile = folder.Files.Add(web.Url + "/" + folder.Url + "/" + sSourceFile, content, true);
                                    web.Folders[sDocLib].Update();

But the code crashes on both the SPFile curFile = web.Folders line for both the commented out line of code and the uncommented line of code.

It crashes with no error when debugging.  I can upload to the document library manually.  I am running this directly on the server and debugging it in Visual Studio 2010.  This piece of code worked fine in SharePoint 2007.

Any ideas what the problem is?