In AnchorElement.Click() there is code that injects a hidden input for an IIS __EventTarget. (I think I was the who added it, years ago.) This addition was short-sighted. SimpleBrowser shouldn't care what the webserver is. If the code in question is needed, the SimpleBrowser consumer should implement it in their solution rather than to have this hack for IIS executed for every SimpleBrowser user regardless of problem space and webserver.