CSP Gateway-Microsoft IIS Error : Not able to have any data exchange through Gateway and also with IRIS.

Web Server Type: Microsoft Web Server: Microsoft-IIS/10.0 .

Error from Gateway  - IRISCONNECT : Error Writing to InterSystems IRIS
Cannot Write Data : IRISconnectSend(): 0 Error Code: 0 (IRISconnectErrorString="SSL/TLS error in SSL_write(), SSL_ERROR_SYSCALL: I/O error (10053)")
lencoded
Accept: text/html,application/xhtml+xml,application/xml;q=0.

Error from HOST System to CSP Gateway : 403 Forbidden Error.

Error from IIS Logs : 403 16

What could be the Root Cause and Resolutions ??