IIS websites accepts asp, aspx formats in it so payloads must be in these formats.
On the other hand Apache servers accept php files....
MSF Modules:
This module create a asp payload and uploads it on the iss web server
exploit/windows/iis/iis_webdav_upload_asp- We need to configure: LHOST, LPORT, RHOST, RPORT, httppassword, httpusername and PATH:
set PATH /<the_web_dav_directory/<shell_name>
This module deletes the payload after gaining a session VERY COOL