[OpenAFS] Windows explorer null pointer v 1.5.07

Christopher D. Clausen cclausen@acm.org
Fri, 25 Aug 2006 16:29:20 -0500

ted creedon <tcreedon@easystreet.com> wrote:
> Christopher D. Clausen wrote:
>>ted creedon <tcreedon@easystreet.com> wrote:
>>>Scenario On a previously "known good" 2003 server:
>>>Open a directory with several hundred photos
>>>Turn thumbnails on
>>>Scroll around and view photos, start drag and dropping to a local
>>>project directory
>>Are the thumbnails being saved (thumbs.db) back into AFS?  I'd suggest
>>turning that off to test.
> Yes thumbsdb is definitely updated each time thumbnails is turned on.
> BTW no NAT, firewall, etc.. on the client, but the server is behind a
> NAT firewall for the external address for eth0,  eth1 is passthrough.
> I.e. the afs server is listening on 2 IP addresses, I've just deleted
> the external IP address from NetInfo and restarted the server and will
> experiment from there.

I'd suggest testing with both client and server directly on the same 
subnet with a single-homed AFS server, just to make sure that isn't the 

Do you get any errors in afsd_init.log or in the event viewer during 
these times?

Are you accessing AFS via a UNC path or via a mapped driver letter?  If 
its a mapped drive letter, how is is mapped?  net use?  afscreds? 

I was accessing \\AFS\acm.uiuc.edu\media\photo\local via that UNC path. 
(BTW, I think you should be able to load that same directory yourself to 
test.)  If you can provide access to your files, I'll test with them 
from here.

What permissions do you have on the files in question?  (I'm assuming at 
least write access if the thumbs.db file was updating.)

How large is your AFS cache?  Default size?  (Mine is 400,000K)  I have 
the stat cache at 10000 which I think is the default.

>>If you copy all of these photos to local disk first, does it work as
> Yes, and it works fine using a local windows directory and also using
> a Linux browser to browse the directory (with thumbnails on) on any
> Linux box. I'm building the project picture directory under Linux and
> dragging it to windows..

Well, Linux is in no way like Windows.

>>I can create thumbnails of a directory with ~550 jpeg files, but I am
>>not saving the thumbs.db file.  I can then drag and drop files to my
>>desktop.  This is on Windows 2003 SP2 beta running OpenAFS 1.5.0600. I 
>>am doing this from the console.  Are you using the console or an RDP
> How does one not create the thumbs.db file?

start -> run -> explorer
Tools -> Folder Options -> View -> check the "Do not cache thumbnails" 

And then delete the thumbs.db file.  It should not show up again.

You don't by chance have multiple Windows computers trying to view 
thumbnails of this directory at the same time, do you?  I suspect that 
this will not work with AFS.


Additionally, I've disabled some Windows 2003 explorer add-ins that may 
be causing problems.  Get http://www.nirsoft.net/utils/shexview.html and 
disable the following:
"Video Thumbnail Extractor"
"Audio Media Properties Handler"
"Video Media Properties Handler"
"Wav Properties Handler"
"Avi Properties Handler"
"Midi Properties Handler"

(the above is everything provided by %SYSTEMROOT%\system32\shmedia.dll)

> Using Windows 2003 Server SP1 OpenAFS 1.5.07, no remote desktop
> session, not console but using Windows Explorer

So you are "on the glass", i.e. a directly attached monitor?