Why does Excel crash with the DDServer test program?
When you put a DDE formula in a cell, Excel asks the server for a number of data formats, starting with XLTable. Excel crashes if the server does not respond in a timely manner. The DDServer test program does not have the format XLTable available, so if you use the formula “=MyService|Test!Count” it puts up a message box asking if this format is to be provided. The delay in answering “No” causes Excel to crash. The solution is to modify the test application so that it automatically rejects any data format that is not built in. You can either remove the event procedures for DDENewDataRequested and DDENewAdviseRequested or make them return without doing anything. This causes DDServer to reject the requests for unavailable data formats immediately. Excel does eventually ask for CF_TEXT which the test program can provide. With this modification, Excel receives data and updates without problems, including a runaway count. Excel sets up a hot link (advise loop) with the DDE server. It uses t
