weird phenomenon
 

I have a client that operates office 2007 standard. Generally when he tries
to open a document, he right clicks and selects open. When he does this, it
starts the excel program, but does not open the document itself. In order
for him to open the document, he has to go to file, open. However, if you
double click on the document, it will open the document in the appropriate
program. Has anyone else experienced this and if so how can I fix this so it
opens the document by right clicking and selecting open?