explorer.exe 100% CPU continually reading PNIDUI.dll

[Tim_Mac]

hi.
i've had a very stable vista installation since RTM. but recently
SearchIndexer.exe started maxing out my CPU, as discussed on this
thread: http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=1597269&SiteID=1
Many other users have the same problem, it's a widespread stability
problem with Search. i've since disabled the search service but
explorer has now taken to maxing out the CPU instead. explorer.exe is
responsive for the first few minutes after log in, but then the
taskbar and start menu stop responding completely and one of the CPU
cores goes to max. i've tried disabling all unnecessary services but
that not improved anything.
i ran ProcMon with a filter on explorer.exe and i see about 3 or 4
entries every second referencing c:\windows\system32\pnidui.dll. it
follows a pattern of CreateFile, QueryBasicInformationFile and
CloseFile. i've included the output from ProcMon below for these
entries. i understand this file simply contains the networking icons,
can anyone explain why explorer should be querying this file in an
infinite loop? i've run virus scans etc., windows defender scans and
everything is fine. i have even installed SP1 RC1 refresh 2 but it
hasn't changed anything.

thanks to anyone who can help me out, i'm dreading the prospect of a
re-install, and since i never even had to re-install XP in its
lifetime that would be a major disappointment for Vista.
tim

Sequence: 1202566
Date & Time: 27/01/2008 11:41:34
Event Class: File System
Operation: CreateFile
Result: SUCCESS
Path: C:\Windows\System32\pnidui.dll
TID: 2720
Duration: 0.0000175
Desired Access: Read Attributes
Disposition: Open
Options: Open Reparse Point
Attributes: n/a
ShareMode: Read, Write, Delete
AllocationSize: n/a
OpenResult: Opened


Sequence: 1202567
Date & Time: 27/01/2008 11:41:34
Event Class: File System
Operation: QueryBasicInformationFile
Result: SUCCESS
Path: C:\Windows\System32\pnidui.dll
TID: 2720
Duration: 0.0000028
CreationTime: 27/01/2008 02:53:08
LastAccessTime: 27/01/2008 02:53:08
LastWriteTime: 19/01/2008 07:36:07
ChangeTime: 27/01/2008 10:03:45
FileAttributes: A


Sequence: 1202568
Date & Time: 27/01/2008 11:41:34
Event Class: File System
Operation: CloseFile
Result: SUCCESS
Path: C:\Windows\System32\pnidui.dll
TID: 2720
Duration: 0.0000054

 

[Tim_Mac]

hi. just replying to myself here. resetting my user profile did the
trick, it must have got corrupt. i followed the instructions on this
blog post: http://blog.tiensivu.com/aaron/arch...rofiles-in-Vista-and-saving-the-contents.html
i still can't use Search or else the CPU problems come back, but at
least Vista holds itself together well enough.

 

[Tim_Mac]

hi sam. many thanks for explaining this, i thought this file was the
source of the problem but you're right i'm sure it was just a lot of
network IO.
thanks
tim