Using Excel 2007, writing a macro and trying to debug it. When any run-time
error occurs and I dismiss it, the macro instantly stops. I used to be able
to see the problem code line highlighted in yellow, fix the problem, and
resume stepping through the macro. It did not happen the last time I wrote
and debugged a macro on the same machine, AND it happens on a co-workers'
machine also on this macro.

I have heard that MS now downloads and installs updates without always
telling us. If that's true, it's possible that a buggy update to Excel was
installed on both our machines. Excel version number is 12.0.6024.5000.