Solution : https://service.sap.com/sap/support/notes/368178 (SAP Service marketplace login required)
Key words : 
web browser sap internet knowledge serverthe iks, directory 'general/misc/km/webserver', struct line parse error - type, thtm  sapkw_layout\ikssearch\style, command 'net start w3svc', dll  sapkw_layout\ikssearch\banner, thtm  sapkw_layout\ikssearch\frameset, sap internet knowledge server, malformed url error message, internet knowledge server
Related Notes : 
       
| 400874 | KW 5.1: Corrections for the IKS | 
| 366597 | SAP KW 5.1 Installation Asia | 
| 359817 | KW 5.0: Displaying KWNet structures with IE4.0 |