If you are on a managed network, Microsoft is trying to be a good corporate
citizen and not provide an easy end-run around corporate policies that are
in place.
I know that there are situations in which this phrasing doesent perfectly
match the situation, though--and there were some messages earlier on
indicating that there was still room for change.
Switching to delta signatures complicated the issue--there's now a base
signature file which is quite large, and a much smaller delta, to get
completely up to date.
It'd probably be of interest to Microsoft if you are able to describe your
situation--do you know why the update process doesn't work for you now?
Within Windows Defender, the autoupdate client is used. In a managed
network, this client may be directed to a corporate server. If that server
is running WSUS, and the server administrator has configured it to deliver
windows defender signatures, that should all just work.
Windows Defender definitions are also available via Windows Update.
However, in a carefully controlled corporate network, access to Windows
Update may also be restricted.
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