DNN re-installation error

I used "web application gallery" and installed DNN suuccessfully (Auto legacy)after couple tries... I wanted to remove and clean up sql server 2008 tables and while deleting tables, I accidentally deleted a table which belonged to successfully installed DNN. So today I decided to delete the DNN using FileZilla FTP, which I did. then I tried web application gallery and istalled DNN again and I got prompted that: "Your application installed successfully. You can view it at: xxxxx" when I click on the link I endup in a page which has URL stating:

h t t p : / / yyyyyyyyyy.com/dotnetnuke/Default.aspx?tabid=40&error=Object+reference+not+set+to+an+instance+of+an+object.&content=0

So it appears to me that "object reference not set to an instance of an object.content" error.

I opened a ticket and was refered to forum.... I already tried ticket suggestions:
1. If you have installed the application to a sub-directory, the folder must be configured as an application starting point using the Web Application Tool at https://my.discountasp.net/webapplication-tool.aspx in your DiscountASP.NET Control Panel.

2. Review the settings that you supplied during the installation/configuration process to make sure that all of the values are correct.

3. Make sure that there is sufficient disk quota assigned to your primary user account as well as for your ASPNET user account through the User/Quota Manager at https://my.discountasp.net/user-manager.aspx in your DiscountASP.NET Control Panel.
and they are all Ok.... any help is appreciated.