That problem has been described on https://launchpad.net/ubuntu/+source/nautilus/+bug/83001 "Nautilus 2.17.90 refuses to open certain text files, claiming: "Error: no application found Cannot open /home/me/file.txt: No application is known for this kind of file." A test case: echo "From Dostoevsky:" > test1.txt echo "In Dostoevsky:" > test2.txt Nautilus correctly opens test2.txt but not test1.txt. I'm using amd64 Feisty with LANG=en-US.UTF-8." That's because the file starting by "From " is detected as application/mbox and there is no editor associated to it. Maybe it would make sense to sub-class the type with text/plain so text editor would be happy to open it?
2007-02-05 Bastien Nocera <hadess@hadess.net> * freedesktop.org.xml.in: Make mbox a sub-class of text/plain so that a text-editor can be used to open it (Closes: #9859)
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