A few days ago users reported problems downloading .zip files in IE 6 from
my website. The site runs IIS 6.0 on Windows Server 2003 SP1. The problem is
new and probably related to the last week security updates since the same
files were working fine before that and nothing was added or changed on the
site (apart from security updates) since a few months ago.

After some poking in the headers and help from Firefox (which works fine) it
appears that the problem is related to the
one described in this thread
http://groups.google.com/group/microsoft.public.inetserver.iis/browse_frm/thread/e65cb6537cec04d9/cc1615e533d26ddc
Surely enough, disabling "Compress application files" makes the problem go
away.
I don't have Sharepoint installed on the site and the .zip files are
downloaded via direct file URL, not through any asp or asp.net page.
Is this a new bug introduced by a security update or something else? How can
I keep the "Compress application files" setting and have IE being able to
download zip files?

--
Eugene

Re: "Compress application files" interferes with zip download, IIS 6 by KL

KL
Tue Oct 24 20:42:24 CDT 2006


Seems like a weird issue but have you tried it in IE7 ? IE7 is quickly
replacing IE6, 3million downloads already since relase and in a few weeks
time it will be on the windows update site so if it works in IE7 I wouldn't
worry about it.

KL.


"Eugene Gershnik" <gershnik@hotmail.com> skrev i meddelandet
news:%23gr0YK99GHA.1220@TK2MSFTNGP04.phx.gbl...
>A few days ago users reported problems downloading .zip files in IE 6 from
>my website. The site runs IIS 6.0 on Windows Server 2003 SP1. The problem
>is new and probably related to the last week security updates since the
>same files were working fine before that and nothing was added or changed
>on the site (apart from security updates) since a few months ago.
>
> After some poking in the headers and help from Firefox (which works fine)
> it appears that the problem is related to the
> one described in this thread
> http://groups.google.com/group/microsoft.public.inetserver.iis/browse_frm/thread/e65cb6537cec04d9/cc1615e533d26ddc
> Surely enough, disabling "Compress application files" makes the problem go
> away.
> I don't have Sharepoint installed on the site and the .zip files are
> downloaded via direct file URL, not through any asp or asp.net page.
> Is this a new bug introduced by a security update or something else? How
> can I keep the "Compress application files" setting and have IE being able
> to download zip files?
>
> --
> Eugene
>
>



Re: "Compress application files" interferes with zip download, IIS 6 by Steve

Steve
Tue Oct 24 21:21:42 CDT 2006

Unfortunately I've seen this with a variety of downloads when compression is
enabled. PDF, XLS are a couple ones that come to mind Firefox was able to
download with compression enabled. Besides disabling compression on the
file or folder, I'm not sure why it fails with IE. Might be worth checking
in an IE newsgroup if there is an IE setting to disable.

--

Thank you,

Steve Schofield
Windows Server MVP - IIS
ASPInsider Member - MCP

http://www.orcsweb.com/
Managed Complex Hosting
#1 in Service and Support


"Eugene Gershnik" <gershnik@hotmail.com> wrote in message
news:%23gr0YK99GHA.1220@TK2MSFTNGP04.phx.gbl...
>A few days ago users reported problems downloading .zip files in IE 6 from
>my website. The site runs IIS 6.0 on Windows Server 2003 SP1. The problem
>is new and probably related to the last week security updates since the
>same files were working fine before that and nothing was added or changed
>on the site (apart from security updates) since a few months ago.
>
> After some poking in the headers and help from Firefox (which works fine)
> it appears that the problem is related to the
> one described in this thread
> http://groups.google.com/group/microsoft.public.inetserver.iis/browse_frm/thread/e65cb6537cec04d9/cc1615e533d26ddc
> Surely enough, disabling "Compress application files" makes the problem go
> away.
> I don't have Sharepoint installed on the site and the .zip files are
> downloaded via direct file URL, not through any asp or asp.net page.
> Is this a new bug introduced by a security update or something else? How
> can I keep the "Compress application files" setting and have IE being able
> to download zip files?
>
> --
> Eugene
>
>



Re: "Compress application files" interferes with zip download, IIS 6 by Eugene

Eugene
Tue Oct 24 22:17:53 CDT 2006

KL wrote:
> Seems like a weird issue but have you tried it in IE7 ? IE7 is quickly
> replacing IE6, 3million downloads already since relase and in a few
> weeks time it will be on the windows update site so if it works in IE7 I
> wouldn't worry about it.

No I didn't try it on IE7 since I don't have it. This is a private site for
a specific audience, not a publicly available one and my users currently all
use IE6. If and when they upgrade to IE7 I'll install it and start testing
with it. Though I'll try hard to switch them to Firefox first ;-)

More importantly the problem is in the IIS, not the browser. It just happens
that Firefox is able to make sense of it (imperfectly - it cannot determine
file size during download) but it doesn't have to.

--
Eugene




Re: "Compress application files" interferes with zip download, IIS 6 by Eugene

Eugene
Tue Oct 24 22:25:57 CDT 2006

Steve Schofield wrote:
> Unfortunately I've seen this with a variety of downloads when
> compression is enabled. PDF, XLS are a couple ones that come to mind
> Firefox was
> able to download with compression enabled. Besides disabling compression
> on
> the file or folder, I'm not sure why it fails with IE. Might be worth
> checking in an IE newsgroup if there is an IE setting to disable.

I have seen similar issues with other file types too in the past but they
had to do with content expiration (I think there is a KB article about it).
This time it happens without any expiration set. Also Firefox too only
barely works. It is able to grab the zip but reports unknown file size
during download.


--
Eugene



Re: "Compress application files" interferes with zip download, IIS 6 by KL

KL
Wed Oct 25 06:04:35 CDT 2006



It isnt a problem in IIS if the FF crap browser handles it correctly, then
it is a browser question, think logically, idiot.



"Eugene Gershnik" <gershnik@hotmail.com> skrev i meddelandet
news:%23Kt6pQ%239GHA.2408@TK2MSFTNGP05.phx.gbl...
> KL wrote:
>> Seems like a weird issue but have you tried it in IE7 ? IE7 is quickly
>> replacing IE6, 3million downloads already since relase and in a few
>> weeks time it will be on the windows update site so if it works in IE7 I
>> wouldn't worry about it.
>
> No I didn't try it on IE7 since I don't have it. This is a private site
> for a specific audience, not a publicly available one and my users
> currently all use IE6. If and when they upgrade to IE7 I'll install it and
> start testing with it. Though I'll try hard to switch them to Firefox
> first ;-)
>
> More importantly the problem is in the IIS, not the browser. It just
> happens that Firefox is able to make sense of it (imperfectly - it cannot
> determine file size during download) but it doesn't have to.
>
> --
> Eugene
>
>
>



Re: "Compress application files" interferes with zip download, IIS by Eugene

Eugene
Wed Oct 25 11:01:37 CDT 2006

KL wrote:
> It isnt a problem in IIS if the FF crap browser handles it correctly, then
> it is a browser question, think logically, idiot.

Whatever institution for mentally retarded had taught you logic had done
a poor job.
For the benefit of those who may think the same way the fact that some
browser can handle X doesn't mean that X is correct behavior. Browsers
contain workarounds for lots of crappy stuff servers send their way.
Please re-read the link given in my original post that summarizes the
problem.

--
Eugene

Re: "Compress application files" interferes with zip download, IIS 6 by Karl

Karl
Wed Nov 29 12:46:47 CST 2006

Eugene Gershnik wrote:

> I have seen similar issues with other file types too in the past but
> they had to do with content expiration (I think there is a KB article
> about it). This time it happens without any expiration set. Also
> Firefox too only barely works. It is able to grab the zip but reports
> unknown file size during download.

I am suffering the same problem.

The reason that Firefox doesn't know the file size is because IIS is
using dynamic compression. They don't know how big the file will end
up being until it is transferred.

--
ATB,
Karl.

Re: "Compress application files" interferes with zip download, IIS 6 by David

David
Wed Nov 29 16:14:25 CST 2006

And IIS uses dynamic compression only because the PDF file is generated
in a way (such as an ASP/ASPX page producing PDF output) such that IIS
does not know how big the size is, either.

If it was a .PDF file sitting on the filesystem, IIS can be configured
to serve it with static compression.


//David
http://w3-4u.blogspot.com
http://blogs.msdn.com/David.Wang
//


Karl Foley wrote:
> Eugene Gershnik wrote:
>
> > I have seen similar issues with other file types too in the past but
> > they had to do with content expiration (I think there is a KB article
> > about it). This time it happens without any expiration set. Also
> > Firefox too only barely works. It is able to grab the zip but reports
> > unknown file size during download.
>
> I am suffering the same problem.
>
> The reason that Firefox doesn't know the file size is because IIS is
> using dynamic compression. They don't know how big the file will end
> up being until it is transferred.
>
> --
> ATB,
> Karl.


Re: "Compress application files" interferes with zip download, IIS 6 by Eugene

Eugene
Wed Dec 06 16:04:55 CST 2006

David Wang wrote:
> And IIS uses dynamic compression only because the PDF file is
> generated in a way (such as an ASP/ASPX page producing PDF output)
> such that IIS does not know how big the size is, either.
>
> If it was a .PDF file sitting on the filesystem, IIS can be configured
> to serve it with static compression.

In my case these are static .zip files sitting on the filesystem.

--
Eugene



Re: "Compress application files" interferes with zip download, IIS 6 by David

David
Wed Dec 06 16:15:58 CST 2006

Whether a resource is considered "dynamic" or "static" by IIS (and
therefore control whether IIS uses "dynamic compression" or "static
compression") does NOT have anything to do with whether they are files
sitting on the filesystem or not.

In other words, ASP.Net pages are also merely static .aspx files
sitting on the filesystem. But surely you consider them dynamic
content.

What actually determines "dynamic" or "static" is the Handler
configured in IIS to handle the resource.

A file is considered "static" only if the IIS Static File Handler
handles the request.

Any other handler is considered "dynamic". In other words, if
ASPNET_ISAPI.DLL is *-scriptmapped or mapped to .zip to handle .zip
files, then .zip files are considered "dynamic".

How does IIS determine handlers? Read this blog entry:
http://blogs.msdn.com/david.wang/archive/2005/10/14/HOWTO_IIS_6_Request_Processing_Basics_Part_1.aspx

Normally, .zip files are handled by the IIS Static File Handler. If you
see "Dynamic compression" affecting .zip resources, then your IIS is
somehow configured such that .zip is not handled by IIS Static File
Handler.



//David
http://w3-4u.blogspot.com
http://blogs.msdn.com/David.Wang
//



Eugene Gershnik wrote:
> David Wang wrote:
> > And IIS uses dynamic compression only because the PDF file is
> > generated in a way (such as an ASP/ASPX page producing PDF output)
> > such that IIS does not know how big the size is, either.
> >
> > If it was a .PDF file sitting on the filesystem, IIS can be configured
> > to serve it with static compression.
>
> In my case these are static .zip files sitting on the filesystem.
>
> --
> Eugene


Re: "Compress application files" interferes with zip download, IIS 6 by Eugene

Eugene
Fri Dec 08 10:13:21 CST 2006

David Wang wrote:
> Normally, .zip files are handled by the IIS Static File Handler. If
> you
> see "Dynamic compression" affecting .zip resources, then your IIS is
> somehow configured such that .zip is not handled by IIS Static File
> Handler.

Ok I am willing to beleive this (though as I stated in the original post I
haven't touched the site in a long while and it definitely worked before).
The next question is how can I find out what if anything is configured to
handle .zip files ;-)

Thanks,
Eugene



Re: "Compress application files" interferes with zip download, IIS 6 by David

David
Fri Dec 08 15:03:50 CST 2006

By reading through the prior mentioned blog file, you should find that
you need to determine the applicable ScriptMaps property for your given
URL and then look through it to determine if it has a mapping for
either '*' or '.zip'.

Locate all ScriptMaps definitions:
CSCRIPT %SYSTEMDRIVE%\inetpub\AdminScripts\adsutil.vbs FIND ScriptMaps

Identify which one is nearest to your URL, and then run:
CSCRIPT %SYSTEMDRIVE%\inetpub\AdminScripts\adsutil.vbs GET
<IdentifiedMetadataPath>/ScriptMaps


//David
http://w3-4u.blogspot.com
http://blogs.msdn.com/David.Wang
//


Eugene Gershnik wrote:
> David Wang wrote:
> > Normally, .zip files are handled by the IIS Static File Handler. If
> > you
> > see "Dynamic compression" affecting .zip resources, then your IIS is
> > somehow configured such that .zip is not handled by IIS Static File
> > Handler.
>
> Ok I am willing to beleive this (though as I stated in the original post I
> haven't touched the site in a long while and it definitely worked before).
> The next question is how can I find out what if anything is configured to
> handle .zip files ;-)
>
> Thanks,
> Eugene


Re: "Compress application files" interferes with zip download, IIS 6 by Eugene

Eugene
Mon Dec 11 01:48:01 CST 2006

David Wang wrote:
> By reading through the prior mentioned blog file, you should find that
> you need to determine the applicable ScriptMaps property for your
> given URL and then look through it to determine if it has a mapping
> for
> either '*' or '.zip'.
>
> Locate all ScriptMaps definitions:
> CSCRIPT %SYSTEMDRIVE%\inetpub\AdminScripts\adsutil.vbs FIND ScriptMaps

Property ScriptMaps found at:
W3SVC
W3SVC/1/root/Exadmin
W3SVC/1/root/Exchange
W3SVC/1/root/ExchWeb
W3SVC/1/root/Microsoft-Server-ActiveSync
W3SVC/1/root/OMA
W3SVC/1/root/Public

As you can see I have Exchange on the same box. In any event the content I
am interested in is in a separate URL root and has nothing to do with it.

> Identify which one is nearest to your URL,

This is W3SVC

> and then run:
> CSCRIPT %SYSTEMDRIVE%\inetpub\AdminScripts\adsutil.vbs GET
> <IdentifiedMetadataPath>/ScriptMaps

ScriptMaps : (LIST) (26 Items)
".asp,C:\WINDOWS\system32\inetsrv\asp.dll,5,GET,HEAD,POST,TRACE"
".cer,C:\WINDOWS\system32\inetsrv\asp.dll,5,GET,HEAD,POST,TRACE"
".cdx,C:\WINDOWS\system32\inetsrv\asp.dll,5,GET,HEAD,POST,TRACE"
".asa,C:\WINDOWS\system32\inetsrv\asp.dll,5,GET,HEAD,POST,TRACE"
".idc,C:\WINDOWS\system32\inetsrv\httpodbc.dll,5,GET,POST"
".shtm,C:\WINDOWS\system32\inetsrv\ssinc.dll,5,GET,POST"
".shtml,C:\WINDOWS\system32\inetsrv\ssinc.dll,5,GET,POST"
".stm,C:\WINDOWS\system32\inetsrv\ssinc.dll,5,GET,POST"
".asax,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
".ascx,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
".ashx,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,1,GET,HEAD,POST,DEBUG"
".asmx,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,1,GET,HEAD,POST,DEBUG"
".aspx,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,1,GET,HEAD,POST,DEBUG"
".axd,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,1,GET,HEAD,POST,DEBUG"
".vsdisco,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,1,GET,HEAD,POST,DEBUG"
".rem,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,1,GET,HEAD,POST,DEBUG"
".soap,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,1,GET,HEAD,POST,DEBUG"
".config,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
".cs,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
".csproj,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
".vb,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
".vbproj,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
".webinfo,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
".licx,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
".resx,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
".resources,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"

Neither .zip nor * is there. :-(

--
Eugene



Re: "Compress application files" interferes with zip download, IIS 6 by David

David
Mon Dec 11 08:27:46 CST 2006

What ISAPI Filters are installed on your web server.
What resource extensions are configured for Dynamic and Static
Compression.

.zip is not configured for compression by default. Neither do ISAPI
Filters exist by default.



//David
http://w3-4u.blogspot.com
http://blogs.msdn.com/David.Wang
//


Eugene Gershnik wrote:
> David Wang wrote:
> > By reading through the prior mentioned blog file, you should find that
> > you need to determine the applicable ScriptMaps property for your
> > given URL and then look through it to determine if it has a mapping
> > for
> > either '*' or '.zip'.
> >
> > Locate all ScriptMaps definitions:
> > CSCRIPT %SYSTEMDRIVE%\inetpub\AdminScripts\adsutil.vbs FIND ScriptMaps
>
> Property ScriptMaps found at:
> W3SVC
> W3SVC/1/root/Exadmin
> W3SVC/1/root/Exchange
> W3SVC/1/root/ExchWeb
> W3SVC/1/root/Microsoft-Server-ActiveSync
> W3SVC/1/root/OMA
> W3SVC/1/root/Public
>
> As you can see I have Exchange on the same box. In any event the content I
> am interested in is in a separate URL root and has nothing to do with it.
>
> > Identify which one is nearest to your URL,
>
> This is W3SVC
>
> > and then run:
> > CSCRIPT %SYSTEMDRIVE%\inetpub\AdminScripts\adsutil.vbs GET
> > <IdentifiedMetadataPath>/ScriptMaps
>
> ScriptMaps : (LIST) (26 Items)
> ".asp,C:\WINDOWS\system32\inetsrv\asp.dll,5,GET,HEAD,POST,TRACE"
> ".cer,C:\WINDOWS\system32\inetsrv\asp.dll,5,GET,HEAD,POST,TRACE"
> ".cdx,C:\WINDOWS\system32\inetsrv\asp.dll,5,GET,HEAD,POST,TRACE"
> ".asa,C:\WINDOWS\system32\inetsrv\asp.dll,5,GET,HEAD,POST,TRACE"
> ".idc,C:\WINDOWS\system32\inetsrv\httpodbc.dll,5,GET,POST"
> ".shtm,C:\WINDOWS\system32\inetsrv\ssinc.dll,5,GET,POST"
> ".shtml,C:\WINDOWS\system32\inetsrv\ssinc.dll,5,GET,POST"
> ".stm,C:\WINDOWS\system32\inetsrv\ssinc.dll,5,GET,POST"
> ".asax,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
> ".ascx,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
> ".ashx,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,1,GET,HEAD,POST,DEBUG"
> ".asmx,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,1,GET,HEAD,POST,DEBUG"
> ".aspx,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,1,GET,HEAD,POST,DEBUG"
> ".axd,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,1,GET,HEAD,POST,DEBUG"
> ".vsdisco,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,1,GET,HEAD,POST,DEBUG"
> ".rem,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,1,GET,HEAD,POST,DEBUG"
> ".soap,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,1,GET,HEAD,POST,DEBUG"
> ".config,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
> ".cs,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
> ".csproj,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
> ".vb,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
> ".vbproj,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
> ".webinfo,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
> ".licx,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
> ".resx,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
> ".resources,C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\aspnet_isapi.dll,5,GET,HEAD,POST,DEBUG"
>
> Neither .zip nor * is there. :-(
>
> --
> Eugene


Re: "Compress application files" interferes with zip download, IIS 6 by Eugene

Eugene
Thu Dec 14 11:03:03 CST 2006

[Sorry for late reply. A case of nasty flu put me completely out of
circulation]

David Wang wrote:
> What ISAPI Filters are installed on your web server.

FrontPage extensions (fpexedll.dll) only

> What resource extensions are configured for Dynamic and Static
> Compression.

Where can I check this? Google brings nothing...

--
Eugene