*** Do NOT DELETE ANYTHING from WINDOWS\$hf_mig$ ***
That subfolder is used by the update to determine which branch of the
update that will be installed during the installation process. There are
2 different branches of an update and without the $hf_mig$ subfolder the
correct branch can not be determined.
The scanning component of WU reads information from the registry and
scans system files to determine which updates are needed. Then it sends
the information back to the update server which in turns pushes 'down'
any updates needed by the system.
More information, probably more than you'd care to read <w>, in
determing which branch of an update will be installed, is viewable here:
MowGreen [MVP 2003-2008]
M. N. wrote:
> When I do a Windows Update, where does the server get the info from my
> computer to decide what updates I need?
> I know that the LIST of previously installed updates in is "Add or Remove
> Programs" list -- but how do they get there? (From the registry? From the $
> prefixed files in the C:\Windows folder?)
> If I delete the $ prefixed files (which use quite a bit of hard drive
> space) in the C:\Windows folder, will this effect the record of previously
> installed updates?