IIS not acepting Json Posts (403) works in IE not Chrome

Hey,

We have a set of IIS web servers behind a cluster of ARR servers.

From IE we can post to a url unfortunatly with Chrome making an identical post we are being returned a 403 Forbidden.

Post Headers from IE

POST https://mydomain.com/signalrTest/myapp/send?transport=foreverFrame&connectionToken=qDGC8ij7AQkV1E1OE5a8nQWir0502Q0Bxws45YIlwD2qJ9DRu0pfXbjd8lBtt2BpjtaKbVdt36ScYlbPBxsxvodD4RRy3vJLSrkhIk8Fq-bDjLaeibRSf8WrXTqtVNUFPiUqfG12TbweYFMDk98OOUMWkBPxZ8qcUU4KfeTdzvlEmsxzaY3mRJQ8n9Y60xD30

HTTP/1.1 Accept: application/json, text/javascript, */*; q=0.01

Content-Type: application/x-www-form-urlencoded; charset=UTF-8 X-Requested-With: XMLHttpRequest Referer:https://mydomain.com/signalrtest

Accept-Language: en-GB Accept-Encoding: gzip, deflate User-Agent: Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.2; WOW64; Trident/6.0)

Host: mydomain.com Content-Length: 96

DNT: 1

Connection: Keep-Alive

Cache-Control: no-cache Cookie : ...

Headers from Chrome

POST https://mydomain.com/signalrTest/signalr/send?transport=serverSentEvents&connectionToken=3nV-ZLdN8oblWHaSaqrgBb9LxtR4cIXCbmf5TMNoEfl8EZN6ArklwUDHwg8y652cASapXfDCV2ndZViBBljgPvQZHu-brm8VnzZx9UkMG64cB95fluZXiO67fRtsc8XH3nQ5TbvrcMklkLwtbrPbLE3ZUVbkqmT5YDqEPaQpX1Zxtjk8u_I1ejkOEPGvMksd0 HTTP/1.1

Host: mydomain

Connection: keep-alive

Content-Length: 93

Accept: application/json, text/javascript, */*; q=0.01

Origin: https://mydomain.com

X-Requested-With: XMLHttpRequest

User-Agent: Mozilla/5.0 (Windows NT 6.2; WOW64) AppleWebKit/537.22 (KHTML, like Gecko) Chrome/25.0.1364.152 Safari/537.22

Content-Type: application/x-www-form-urlencoded; charset=UTF-8

Referer: https://mydomain.com/signalrtest

Accept-Encoding: gzip,deflate,sdch

Accept-Language: en-US,en;q=0.8

Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3

data=%7B%22H%22%3A%22chat%22%2C%22M%22%3A%22Send%22%2C%22A%22%3A%5B%22%22%5D%2C%22I%22%3A7%7D

Any ideas greatly appreciated.