Why don ISAPI_Rewrite and IISPassword get on well?
The issue is that IISPassword and ISAPI_Rewrite use the same configuration file name – .htaccess, but unlike ISAPI_Rewrite, IISPassword fails if any unknown directives are found in it. So to avoid conflicts you need to change configuration file name for either product. To change configuration file name for ISAPI_Rewrite use AccessFileName directive in httpd.conf file.
