I must have done something to Ubuntu 12.04 on my latop because a few weeks ago, various applications (Chrome, Calibre, etc.) have stopped opening documents (like PDFs, zip files, etc.). What happens when these applications try to open a file is that I get a new Nautilus window that is opened to the directory that holds the document.
If I then double click the document in the nautilus window, the appropriate app is opened up (Adobe Reader, File Roller, etc.). Because of this, I don't think the issue is with the association between file types and apps, but I could be wrong.
I have another desktop system running 12.04 where everything works as expected.
What would cause this and how to I fix it?