I have a solution to my own question here, but if anyone has anything to
add, I would appreciate it.

When trying to expand service pack updates, or other .exe compressed files,
under Windows it never seems to work. I now always use Winrar to decompress
these files in to a folder and then copy it on to the server. Sometimes, if
I double click on the file from a workstation when it is on the server, it
decompresses and everything is fine. In the past, I have had issues where it
starts but then corrupts after a while, but these days it seems to work.
However, if I double click on the .exe file under Windows (without using
Winrar) a command prompt opens and a decompressing (can't remember the
details)message is displayed, but after a few minutes the command prompt
closes and the original file is there, but has not been decompressed.

Question: Can anyone give me a definitive reason for this? Is there an
official method of dealing with these files such as the latest large SP4a
download? I have always had issues over the years, and the degree of these
issues has slightly changed but basically the same underlying issue remains.
You cannot simply download a compressed update from Novell and copy it to a
Windows desktop in to a folder, double click on it and it successfully