4D web server protected by a proxy server - pdfs don't come through

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4D web server protected by a proxy server - pdfs don't come through

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tl;dr

PDFs served by 4D v12 open in a new  browser tab as expected from the same
machine, and also from other machines on the LAN.

When accessed from a machine in the DMZ, not on the LAN, we can navigate
the site, but the PDFs don't come over.

It seems like the OS firewall or WebRoot antivirus tools may be blocking it
on the DMZ machine, but we can't tell.

Any ideas?



details:

We have several 4D v12.6 servers with web servers running and a single
Apache server providing security, since v12 is too old for that.

These are very simple web servers - they provide lists of PDFs, and you
click on the links to open them.  The backend is using Active4D.  The same
basic setup has been used for about 10 years.

Until recently, this has worked well.  Yesterday, the customer said the
PDFs aren't opening for users logged in over the internet.

When we test, if we run a browser inside the LAN and connect directly to
the 4D server, it works fine.

If we run a browser on the proxy machine in the DMZ, we can connect
directly to the LAN 4D web server and use the site, but the PDFs fail to
load.  We get the same behavior connecting over the internet with the
Apache proxy in the middle.

There is an error message in the browser Console panel:
"Resource interpreted as Document but transferred with MIME type
application/pdf"


The link on the web page looks like this:
<a href="/docs/GPB-Auto%20%5B1%5D/Aixen%20International%20S.
A%20%5B6%5D/Statements/September-2016%20Account%20Statement%20-%20Axien%20International%20S.A..pdf"
target="_blank">Account Statement - Axien International S.A.</a>


Occasionally the PDF makes it through.  We've tried changing the target
attribute so it downloads instead, but if the file comes down, it is
corrupted and unreadable.
We get the same behavior with Chrome, Firefox, IE, and Edge.

In all cases, the web site works and behaves normally except for accessing
the PDFs.

It seems there is something about the proxy server machine that is causing
the problem.  Maybe an OS update that silently changed some security
settings, or a tool that is installed on the machine called WebRoot.


Thanks!

Jim Hays
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Re: 4D web server protected by a proxy server - pdfs don't come through

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did you Google for that error message?

2017/06/01 6:52、Jim Hays via 4D_Tech <[hidden email]<mailto:[hidden email]>> のメール:
"Resource interpreted as Document but transferred with MIME type
application/pdf"



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Re: 4D web server protected by a proxy server - pdfs don't come through

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Yes.  Most answers say something like replace (pseudo code) target="_blank"
with target="_document", and make it download instead of display in
browser.  It has the same problem though.
I few messages said there was a bug in Chrome some years ago, but this
happens with multiple browsers.

Tomorrow I'm hoping the IT person will turn off the firewall and anti-virus
temporarily and we'll see if that makes a difference.

Thanks,

Jim

On Wed, May 31, 2017 at 6:12 PM, Keisuke Miyako via 4D_Tech <
[hidden email]> wrote:

> did you Google for that error message?
>
> 2017/06/01 6:52、Jim Hays via 4D_Tech <[hidden email]<mailto:4
> [hidden email]>> のメール:
> "Resource interpreted as Document but transferred with MIME type
> application/pdf"
>
>
>
> **********************************************************************
> 4D Internet Users Group (4D iNUG)
> FAQ:  http://lists.4d.com/faqnug.html
> Archive:  http://lists.4d.com/archives.html
> Options: http://lists.4d.com/mailman/options/4d_tech
> Unsub:  mailto:[hidden email]
> **********************************************************************
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Re: 4D web server protected by a proxy server - pdfs don't come through

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It turns out the blocked/corrupted PDFs were caused by Cisco Meraki
firewall malware protection when they traveled from LAN to DMZ.

On Wed, May 31, 2017 at 6:23 PM, Jim Hays <[hidden email]> wrote:

> Yes.  Most answers say something like replace (pseudo code)
> target="_blank" with target="_document", and make it download instead of
> display in browser.  It has the same problem though.
> I few messages said there was a bug in Chrome some years ago, but this
> happens with multiple browsers.
>
> Tomorrow I'm hoping the IT person will turn off the firewall and
> anti-virus temporarily and we'll see if that makes a difference.
>
> Thanks,
>
> Jim
>
> On Wed, May 31, 2017 at 6:12 PM, Keisuke Miyako via 4D_Tech <
> [hidden email]> wrote:
>
>> did you Google for that error message?
>>
>> 2017/06/01 6:52、Jim Hays via 4D_Tech <[hidden email]<mailto:4
>> [hidden email]>> のメール:
>> "Resource interpreted as Document but transferred with MIME type
>> application/pdf"
>>
>>
>>
>> **********************************************************************
>> 4D Internet Users Group (4D iNUG)
>> FAQ:  http://lists.4d.com/faqnug.html
>> Archive:  http://lists.4d.com/archives.html
>> Options: http://lists.4d.com/mailman/options/4d_tech
>> Unsub:  mailto:[hidden email]
>> **********************************************************************
>
>
>
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