I am on a VPS through Network Solutions.
I made a site, it is pretty much 100%.
I decided to make a subdomain --> dev.productionsite.com
I copied my tables into my new database called development.
I FTP'd my copied joomla files using FILEZILLA to my subdomain folder.
Everything worked, I see my FAVICON, as well it is not a configuration.php issue, I changed all that info, and double checked by changing it, and getting a CANNOT ACCESS MYSQL -- whatever. So my configuration is good, I just have a BLANK SCREEN. No errors. Just Blank.