From what I gather the service or process is a valid one but one that
is often used by adware and spyware. But that doesn't mean that it is
only used by crapware, it could be used by other software for perfectly
valid reasons. My informations says: " khost.exe is a secure data
delivery application by Kontiki Inc. which delivers data such as images
and files to secure servers for sharing. This is a non-essential
process. Disabling or enabling this is down to user preference."
You will have to find out what is using it, maybe things like Kodak
image sharing or Kazzaa or the likes. I'm not implying that these
(Kodak, Kazzaa) are using it but these are the type of applications that
come to mind that might be using this.
Find out what is starting when you boot the pc or explore the process
tree to pin it down. These utilities may help:
http://members.lycos.co.uk/codestuff/
http://www.sysinternals.com/Utilities/Autoruns.html
http://www.sysinternals.com/Utilities/ProcessExplorer.html
For all it's worth I wouldn't want "sharing" applications running on my
pc without knowing what they are and without having specifically
authorized them, presents considerable security risks! Find the culprit
and change the startup behaviour of the program or get rid of it if you
don't use it.
John