[mapserver-users] Mapserver WMS server, IIS and wrong content-type

Jeff McKenna jmckenna at gatewaygeomatics.com
Mon Jul 4 10:56:07 EDT 2011

Hello Oliver,

Here is some more info, taken from 
http://www.libpng.org/pub/png/pngstatus.html :

"As a related item, note that Microsoft's Internet Information Server 
(a.k.a. IIS) shipped by default without an explicit MIME type for PNG 
images until version 6, which effectively meant that it treated PNGs as 
application/octet-stream rather than image/png. Not surprisingly, this 
affected only non-Microsoft web browsers connecting to IIS servers; they 
rightly refused to display such mislabelled PNGs. Fortunately, Microsoft 
did finally correct the problem with the release of IIS 6.0 in 2003, and 
a fix is available for older versions (at least for version 4.0)."

So that goes along with my initial ideas.

Anyway those are my quick thoughts on your problem with your client's 
IIS instance.  If you want to contact me directly and we can work 
through this together with your client please do.


Jeff McKenna
MapServer Consulting and Training Services

On 11-07-04 11:39 AM, Oliver Christen wrote:
> Hi Jeff,
> I do not have my hand on that server so I cant test it myself, I was
> only relaying the question.
> I did read the article but I failed to see how it would solve the problem.
> I will relay that info to the server admin and see if it works.
> thank you
> best regards
> Oliver
>> Hello Oliver,
>> It can't hurt to try the steps outlined in that link I provided. It
>> would answer the questions you posed in your last email.
>> -jeff

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