Does anyone know why the following line might cause a Runtime Error?

Application.Calculate

I understand that the surrounding code may be suspected to be involved, but
running the same Macro twice will not necessarilly have a problem.
Additionally, this has occurred in other Sub routines on the same code. The
runtime error pops up, I go to Debug and that line is highlighted. If I hit
F8, it runs that line with no problem....or if I hit F5, it continues
running.

Any ideas?

Thanks,
Paul

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