Thank you.
Can you confirm if the DNS/DHCP entries should have wpad.dat on the end of should they just be the URL where to find it?
Thanks
Glen
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Browse All TopicsHi All,
I am trying to configure WPAD.DAT as an automatic proxy configuration.
We have had a working PAC file for some time, so I have renamed this to wpad.dat and placed it on an internal webserver.
I have also configured DHCP with option 252 called WPAD with text http://webservername/wpad.
I have also configured a DNS entry with a CNAME record called WPAD for http://webservername/ and again I have also tried it with http://webservername/wpad.
I seem to get logs in the W3SVC1 folder on the webserver indicating that the file has been requested log entry here:
2009-06-01 07:42:02 W3SVC1 serverIP GET /wpad.dat - 80 - clientIP Windows-Update-Agent 404 3 64
However when I open the browser on the client machine it doesn't work.
If I try to put the URL into the web browser I get a 404:
HTTP Error 404 - File or directory not found.
Internet Information Services (IIS)
If I rename the file to a txt file it opens OK.
Anyone got any ideas?
Thanks
Glen
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I would recommend using the DNS for WPAD as there are some limitations to using DHCP, especially with older clients.
The CNAME record you create should just point to the hostname of your IIS server hosting the WPAD.DAT file. No "http://" or "wpad.dat" etc. just the WEBSERVERNAME.
If you are using DHCP however, you should use the full URL for the WPAD file "http://webservername/wpad
Hope this helps.
Raj
OK, I think I have got to the bottom of it.
It works OK with Windows XP.
I tried it on Windows Vista and Windows 7 both with IE8 and it didn't work, however if I logon to the computer as a user that hasn't logged on to the user and doesn't have a roaming profile, make the setting and it works OK.
I have just cleared my local profile completely (and broke it as it's Windows 7) and it seemed to work when I logged back in.
Any ideas why it is not dynamically changing on Windows Vista/7?
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by: Raj-GTPosted on 2009-06-01 at 01:21:35ID: 24515703
You need to register .dat as a valid MIME type in IIS.
toconfig" for MIME type.
Open IIS Manager and right click SERVERNAME and select properties. Edit MIME Types and add .dat as a valid MIME type. Use .dat for extension and "application/x-ns-proxy-au
Restart IIS and it should work as it should.