I have a number of regularly-used Excel 2010 workbooks with large numbers of formulas and user-defined macros. In the course of running any one of them, I have recently started to find myself looking at unmoving, semi-dimmed out, worksheets with the message at the top of the window "Excel not responding".

Once this happens nothing enables me to interrupt the ongoing process, not Escape or CTRL-Break or even Alt-F4. I can either just wait (which can take minutes if at all) or use Windows 7 Task Manager to close the application. Microsoft Office Support have used their tools to try to clear this up - but to no effect.

What I would like to do is to monitor and record Excel's actions/events when this occurs, something I could do very laboriously by sending a debug.print message each time any macro is entered or exited. But before I start on that task, I would like to know if there are any relevant automatic facilities that can be invoked to write a log-file from the moment a workbook is opened.

All suggestions or ideas are welcomed.