just to add more info, right now if I try http://domain1.com it is redirecting to http://domain1.com/dotnetnuke and display 404 error at the same time http://localhost directly on the server displays IIS welcome page

Your dnn install on domain1 is not root.  Further your desired portal is 1 not the default 0

I use GoDaddy for many sites, and GoDaddy does not support root dnn installs.  Supposedly you can hack it, but they don't support it.

To accomplish what you describe on GoDaddy, I buy a meaningless domain, call it XXX.com.  I make it the primary domain for the hosting account.  Your files would then reside at XXX.com/dotnetnuke and your target site at XXX.com/dotnetnuke/portal1

Make domain1 a portal alias for portal1 on your dnn instance (while logged in as host)

Forward your domain1 to XXX.com/dotnetnuke/portal1

GoDaddy allows you to map/assign any non-primary domain on an account to any folder under the primary from their console w/o having to fuss with the forwarding, though it works the same way...

To see in action, www.brooksfloors.com and www.brookshardwoodfloorrefinishing.com both are forwarded/mapped to directories/folders under  brookshardwoodfloors.info [I typically use /dotnetnuke, /asp, or /secure as my dnn instance directories]

Hope this helps.

Bob H.