[X Newbies] "...disk is in use" But by what process??

[James S Jones]

Here's a typical scenario for me.

I download a new or updated application. A disk image mounts. I 
double-click a PDF or text documentation file for the app. Acrobat 
Reader or TextEdit opens with the document and I skim the info to 
decide whether I'm interested. I then close the document, but not the 
"reader". Next, I try to eject the disk (image) and can't--it's in use.

The solution is to close the application that was launched by opening a 
file on the disk (that refuses to be ejected). Quit Acrobat Reader, 
etc, and the disk is no longer in use. If the reader app had already 
been running when the file on the disk was opened, you will not have 
this problem.