NtfsDisableLastAccessUpdate

[Rob Burnett]

After an in-place upgrade from Windows Media Center 2005 to Windows Vista
RC2 Ultimate (build 5744), the following key and value were created on my
box

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\FileSystem
NtfsDisableLastAccessUpdate
REG_DWORD 0x01

What's up with this registry being created during setup? Is it OK to change
it back to 0x00 ?

Neither the key nor the value were present prior to upgrade. The behavior
seems to be identical to that in Windows 2000 described here.
http://www.microsoft.com/technet/prodtechnol/windows2000serv/reskit/regentry/46656.mspx

Only other item of note is that this MCE box only had one member of the
Users group and only Built In as an Administrators group member prior to
upgrade. After the MCE box was initially setup after purchase last year, the
other Administrator was demoted to Users group only and that is who we used
to auto logon as. After upgrade to Vista we have to turn UAC off and logon
as the Administrator to do anything.

BTW, most other areas Windows Media Center in Vista RC2 is greatly improved.
The in-place upgrade was the only method I could see to allow previously
installed codecs to still work. If I tried format and reinstall, when it
came to adding the codecs, install always failed, they were DiVX and AVC
H.264. I'm still struggling with UAC in other areas but maybe will get used
to it. We'll miss some of the new Vista MCE features if we can't eventually
get the rights and permissions set up.

 

[Jimmy Brush]

Hello,

After upgrade to Vista we have to turn UAC off and logon
as the Administrator to do anything.

What specifically were you prevented from doing?

 

[Rob Burnett]

What specifically were you prevented from doing?

Preserve my sanity while configuring the machine in a timely manner.

 

[Jimmy Brush]

In that regard ... good luck.

I couldn't find any information specific to that registry key for Vista ...
my guess would be they simply enabled it by default because it can increase
performance with only a slight chance of application compatability issues. I
can't imagine changing it back to 0 would cause any problems, assuming that
NTFS still allows this functionality.

 

[Jill Zoeller [MSFT]]

We're going to work on a blog post on this to get the word out. In the
meantime, here's a quick explanation and a pointer:


Last Access Time is a file attribute that's updated when a file is accessed
or otherwise touched. This is often confused with the Last Modified Time
which is only updated when the file changes. It has a loose granularity
that only guarantees that the time is accurate to within one hour.
Generally, it is only used in server or enterprise scenarios. To improve
performance for Windows Vista, Last Access Time updates will be turned off
by default. If your application or product relies upon this value, you can
enable it via the following registry key.


Key Name: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\FileSystem
Name: NtfsDisableLastAccessUpdate
Type: REG_DWORD
Value: 0 to Enable or 1 to Disable (new default)


Some helpful links (not Vista-specific though):
http://technet2.microsoft.com/Windo...7f13-4ac3-8da8-48ebd60b44471033.mspx?mfr=true

https://www.microsoft.com/resources.../proddocs/en-us/fsutil_behavior.mspx?mfr=true