iis 7.5 - Umbraco - two websites on single Umbraco instance - 2nd site gives 404 -

i've set 2 umbraco websites on single instance of umbraco (v 4.7.1.1). if visit 1st website (which listed first under 'content' node):

www.mysite.com

... correct homepage (the homepage nested @ content > www.mysite.com > global > homepage)

however when go 2nd website (listed directly under 'content' node, below 1st website):

m.mysite.com

... 404. homepage site nested same way (content > m.mysite.com > global > homepage), , can homepage using address m.mysite.com/global/homepage. i've checked/tried following:

• the 'manage hostnames' configuration both sites in umbraco correct
• i have usedomainprefixes set true in umbracosettings.config
• there no redirects in iis 7.5 redirecting 2nd domain name
• my bindings correctly set in iis
• the default document in iis 7.5 umbraco instance set default.aspx. i've moved top of list
• the hosts file on web server pointing m.mysite.com correct ip
• the homepage 2nd site using template
• tried adding property doctype that's used root node 2nd 'website', alias 'umbracoredirect' , type 'content picker', , pointing node homepage (apparently method can have problems anyway, if works)
• i've tried adding property doctype that's used 'global' node, alias 'umbracointernalredirectid' , type 'content picker', , pointing node homepage
• tried adding property doctype that's used 'global' node, alias 'umbracoredirect' , type 'content picker', , pointing node homepage (apparently method can have problems anyway, if works)
• tried putting homepage 2nd site directly below root node of 2nd site (although 'link document' page comes m.mysite.dev/test/)
• tried adding umbracointernalredirectid website node itself, point new homepage directly below root website node
• tried iisreset , flushing dns resolver cache, site still gives 404
• tried republishing both websites
• separately re-published nodes in 2nd website, , separately published new homepage created below site root node
• edited web.config file
• double-checked everything, tried re-applying 'manage hostnames' configuration, tried re-doing 'umbracointernalredirectid', republishing site , restarting iis again

i discovered in physical folder structure umbraco installation there's file config\urlrewriting contains following:

destinationurl="~/global/en"  rewriteurlparameter="excludefromclientquerystring"  ignorecase="true"/> 

so if change things page want homepage mobile site page 'en' in following structure:

site 2

• global

  • en

it works, since m.mysite.com points page @ http://m.*mysite*.com/global/en.

here's original steps needed working:

• add a-record domain host 'm' (ie. m.mysite.com)
• right click m.mysite.com umbraco site > manage hostnames - add m.mysite.com
• add binding umbraco website, m.mysite.com
• edit umbracosettings.config (in w3cms\config) - set true
• may need restart iis settings take effect