Ethernet Client Get

I am trying to send data from arduino to my local system which is running a iis server and c# web api application and exposes a get request

the api on system looks like this http://localhost/iot/data.asmx/GetData?tagid=123456 and it works correctly.

now i am trying to run a bare minimum ethernet client to send this test data to the server, the code

if (client.connect("", 80)) {
    client.print("GET /iot/data.asmx/GetData?tagid=123568");
    client.println(" HTTP/1.1 ");
    client.println("Content-Type: application/x-www-form-urlencoded");

the serial output prints connected but then nothing happens. the data is not getting logged in the server.

i hope this should be a straight forward one, but i am completely unable to find anything, neither the api is throwing an error nor the arduino.

any idea?

P.s i switched off the firewall also.

    client.print("GET /iot/data.asmx/GetData?tagid=123568");
    client.println(" HTTP/1.1 ");

Why exactly is that empty client.println() between the two lines that build the request line?

If you must have HTTP 1.1 support, you should add a "Connection: close" header.

And you should read the server response, otherwise the connection might be closed before the request is handled. I don't know how IIS is reacting on such behavior, in my experience it's not very tolerant.