#keep-alive

This is a specific problem for Cinema 4d r16 team render.

After an update I got this error message with "keep-alive", and long story short, I found a solution!

Open Cinema Team Render Client, open preference, look down the page and find "Open Preference Folder..." 

Hit the button and go back in folder history and find the Maxon folder. Delete all the stuff after Maxon/ to reset all the Client settings. All these files are recreated after a Client restart.

Fix all your Team Render settings. Restart Cinema 4d. And KABOOM! it's back.

Change HTTP header through .htaccess Keep-alive is enabled by explicitly requesting it via your HTTP header. Doing so will override any higher settings. If you do not have access to your webserver config file you can add HTTP headers yourself using an .htaccess file.

<ifModule mod_headers.c> Header set Connection keep-alive </ifModule>

Adding this to your .htaccess file will add keep alive headers to your requests, which will over ride most webserver or host limitations.

Enable keep-alive in Apache

If you are able to access your Apache config file, you can turn on keep-alive there. The applicable sections are shown below

Things you can learn by reading issues. guypod's answer to Paul Irish

I am strongly in favor of turning on keep-alive, even by default. Here are some key reasons why.

1) TCP Connect is expensive. There are many stats which are more data-backed out there, but even a quick test on WebPageTest shows an average connect time of 100ms for Cable speed with 28ms latency. Adding 100ms to the time to fetch every resource is a lot, even if some of those are happening in parallel.

2) On Mobile networks, TCP Connect is even more expensive. The same test from above, but slightly modified to use a 200ms latency connection raised the average connect time to 234ms. That's a lot of time.

3) Keep-Alive is required for the use of HTTP Pipelining. Most mobile browsers use HTTP Pipelining, and it looks like Chrome will enable it by default soon. Clearly the data these browser makers have indicates piping requests is good, and closing the connection each time will take away that value.

4) As @safruti recently reminded me, not knowing your content length (e.g. when gzipping content) does not require closing the connection if you use chunked encoding. So perhaps changing .htaccess should come with some other changes to enable chunked encoding if it's not already on...