Hello,

do one effort and set bytes instead of chars, you can be maybe more sure about correct output from PLC port. In case of not sure, set PC app (Hercules as example) as Server/receiver of message to see that all is ok. then send this via http Port and you'll see. If you will have same answer then problem is as message describes.

I see your post date. Look, your message from Server is looks like ok and your message is also correct with internal structure because that message simply shows that about directory problem. I recommend to do that byte test for sure if you still have problems but I expect your wrong request as is.