Before launching the relevant application for the document, a 'test -f' or
similar should be done to determine that the document has not been moved or deleted.

1.  If the document exists and is readable, launch the Application.

2.  If the document is not accessible due to permissions:

"You do not have permissions to open the file [/path/to/document].  To access
the document you may need to log in as a different user or contact your System
Administrator."

3.  If the document is not accessible because the filesystem is not mounted:

"The document [/path/to/document] is not accessible due to the file system
[/filesystem] not being mounted.  Please mount the file system, or ask your
System Administrator to do so."

4.  If the document seems to have been moved or deleted, display the message:

"The document [filename] no longer exists in the directory [/path/to] and has
probably been moved or deleted.  If the document was stored on a floppy disk,
rewritable CD/DVD, USB drive or other removeable medium, please ensure the
correct medium is inserted."

And then for option 4, it would be fantastic if it also offered to invoke a mini
Search utility to see if the document had simply been moved elsewhere in the
filesystems.  The utility could use a basic filename check to find the closest
match to the stored document name.

If the user opts to not invoke the search utility, or if the search does not
find the file, the gnome-menu should display a user-friendly message stating
that the file could not be found.

"No documents resembling the document [/path/to/document] were found"

It should then prompt the user whether they would like to remove the entry from
the 'Recent Documents' menu.

"Would you like to remove this document from the Recent Documents menu?"

Other information: