Java binfmt is trying to open files instead of Office 2007
Some users report that associations don't work for Office 2007 documents (i.e. double-clicking the document in file browser doesn't work) although these documents open fine in Office 2007 (i.e. "file"->"open" inside the program works) and other applications do work. You can diagnose the issue by running the following in a terminal
Note that the above command will generate a file called "logname" in your home directory, and also the "/opt/cxoffice/bin/cxstart" command assumes that you installed Crossover from the .deb/.rpm package, rather than the .bin file.
The telltale sign of the error is a line:
invalid file (bad magic number): Exec format error
A component of Java (binfmt) detects Office 2007 files (docx, pptx, etc) as its own and passes them to jexec which then refuses them as not being executable files.
The workaround is to remove binfmt and eliminate the conflict.
sudo update-binfmts --remove jar /usr/lib/jvm/java-6-sun-18.104.22.168/jre/lib/jexec --package sun-java6