Header - Transfer-Encoding:chunked

Hi guys,

This probably isn't the correct list to post this question as I'm pretty sure it's not CB related, but you guys are some of the smartest CF'ers out there. I was trying to find another CF list to post this on but couldn't find one. If you know of a general/advanced CF list, please send over! I'll post the issue anyways in case someone has encountered this before

I've been trying to narrow this down to being a CF or IIS7/compression issue....

On my staging server when I make a request to a page there is an HTTP header returned called - Transfer-Encoding:chunked and no Header returned for Content-Length. This is causing part of our application to not "play-well" with a third-party service that talks to our app. Staging is a single instance of CF multiserver and IIS7.

On our production server, the exact same codebase is running, but it's CF multiserver with 3 instances and IIS7. When I call the same page on production the transfer-encoding header is not returned and content-length is returned. I've gone through numerous IIS articles talking about disabling compression but to no avail. I'm trying to figure out if this has something to do with lower level CF config setting, but for the life of me can't determine why this is happening.

If anyone has experienced this before I'd love to know more, otherwise if you can recommend another list to post this on that too is greatly appreciated.

Thanks guys.


Do you have your web.config in version control and consistent in both environments?

Perhaps this command will help?

appcmd set config /section:asp /enableChunkedEncoding:True|False

Yep. Tried that and it didn’t affect anything. What’s weird is this setting is set to true on the production server.

The web.config is different on production so i’ll try replacing the web config. There are a few settings that are custom to production so i’ll have to make sure to not copy those.

Thanks Aaron, and Dorioo for the link. I’m going to post to CF-Talk as well.


I think this issue is isolated to IIS. Using Fusion Reactor, you can see the headers set by ColdFusion by a response prior to being received by IIS to then be returned to the client. I do have a chunked header on my local server here, however, ColdFusion did not apply it:

ColdFusion Headers

Hi Aaron.

I agree, this seems to be IIS and not CF. Good to know FusionReactor gives you that level of granularity! I need to check it out.



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