Import local "HTTP / 1.1 Error 400 Bad Request"

Hello,

I need your help for a problem when importing local .ocs files!

I still have this error "HTTP / 1.1 Error 400 Bad Request" ...

I'm relying on OCS version 2.3.1 on an Ubuntu 16.04.3 server.

I tried several times on machines in different ways and impossible to arrive ... 

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I've been stuck for quite some time and I'm breaking my head on it. Image may be NSFW.
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I thank you in advance for your help! Image may be NSFW.
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