Yup, I fully understand what it is that you're after and why, I just need to know all the potential errors that Windows can throw up if a program tries to open a file that it's using.
'Access is denied' is an obvious one.
There could also be ones like 'sharing violation' etc.
I need to build up a rough list so I know exactly what to check for and what therefore what to apply the 'ignore' to automatically.