Windows Tip Sheet
Unknown Displeasures
Migrating to XP SP2 can sometimes leave you a mess of unknown devices.
This tip is part 2 in a series of 5 on living with Windows XP Service Pack
2.
Upgrading to SP2 left one of my customers with a dozen machines suddenly complaining
about unknown devices in Device Manager. I mean, a lot of them—so many
that we both knew something was wrong. Having had zero problems with SP2 myself,
we started searching for oddities on his machines.
Of course, we had no luck. But then I ran across a Microsoft MVP-authored Knowledge
Base article that suggested registry permissions were at fault. Aha, we thought—we
knew my customer had been messing around with registry permissions in an attempt
to lock down permissions for some reason or another. It wasn’t something
I’d felt comfortable with, but it was his network and I don’t do
24x7 support, so why not?
The fix is to put the permissions back the way they were (turns out this particular
subkey had been modified by mistake anyway). You’ll either need to be
a member of the local Administartors group to run this, or schedule it to run
under Task Scheduler with admin credentials. You’ll also need the SubInAcl.exe
command-line utility.
subinacl /subkeyreg
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum
/grant=Administrators=F
/grant=System=F
/grant=everyone=R
Now Windows will be able to properly enumerate devices and the problem should
go away.
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About the Author
Don Jones is a multiple-year recipient of Microsoft’s MVP Award, and is Curriculum Director for IT Pro Content for video training company Pluralsight. Don is also a co-founder and President of PowerShell.org, a community dedicated to Microsoft’s Windows PowerShell technology. Don has more than two decades of experience in the IT industry, and specializes in the Microsoft business technology platform. He’s the author of more than 50 technology books, an accomplished IT journalist, and a sought-after speaker and instructor at conferences worldwide. Reach Don on Twitter at @concentratedDon, or on Facebook at Facebook.com/ConcentratedDon.