Does he have a scheduled scan set to run every few hours? In Tools, Options
(scroll down!) there is a setting to update definitions before a scheduled
scan. This may be what is happening. It should be possible to disable
update within the app completely, I believe.
He might be interested to know that the latest definitions will always be
available at the Microsoft Security portal:
www.microsoft.com/security/portal However, those definitions will always be
complete, so the download size is larger than if they are acquired via
WindowsUpdate or AutoUpdate (or may be, anyway.)
"Pat Willener" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> An acquaintance of mine sits in a country where broadband connections are
> virtually unknown, and he has to use a slow dial-up connection.
>
> Windows Defender seems to want to connect via MpCmdRun.exe every few hours
> to check for updates. He already has Windows AutoUpdate disabled, but he
> also needs to disable Windows Defender's own update check.
>
> Is there a way to disable these automatic update checks? He wouldn't mind
> to implement this via a registry change, if WD options do not allow for
> this.
>
> Thanks!