I elected to delete the previous version (v2.2.1) and then reinstall
v2.2.4, which was probably unnecessary bother.
After removing the older version with rpm -e <filename>, when I attempted
to install the new one, I received the following error message:
*****
No precompiled module for this kernel found -- trying to build one.
Messages emitted during module compilation will be logged
to /var/log/vbox-install.log.
Compilation of the kernel module FAILED! VirtualBox will not start until
this problem is fixed. Please consult /var/log/vbox-install.log to find
out why the kernel module does not compile. Most probably the kernel
sources are not found. Install them and execute
/etc/init.d/vboxdrv setup
as root.
insserv: script lpd: service cupsd already provided!
*****
Inspecting the log entry, on the other hand, tells me a similar, but
different, story:
*****
** Compiling vboxdrv
Makefile:172: *** Error: unable to find the include directory for your
current Linux kernel. Specify KERN_INCL=<directory> and run Make again.
Stop.
*****
These are two different diagnoses. Furthermore, in each of the
suggestions, there are things I don't know how to do: