We are having issues with our upgrade from CF9 to CF10. Our plan was to install CF10 then uninstall CF9. We were able to successfully install CF10 but when we turn off CF9 we are unable to access our CF sites. Oddly enough, we are still able to access the CF10 administrator but we cannot access any of our CF sites. Suggestions?
You need to remove the CF9 connectors from your websites using the CF9 WSCONFIG tool, then make sure your connectors are working for CF10.
As i can see problem is in hosting both the coldfusion server on webserver.If you are hosting your website in ubuntu. Then you can flollow this link http://ashishtondon.blogspot.in/2012/05/how-to-host-more-then-one-coldfusion.html
If it is a Windows OS then first create different two local websites on different ports then while installing coldfusion 10 it will ask for selection of localhosts now give port 81 to the cf 10 if your cf 9 is on default port 80.
then check , for CF9 - localhost:80/cfide/administrator/index.cfm
for CF10 - localhost:81/cfide/administrator/index.cfm