Upgrading from 1.7.2 to 2.0.2 Problems

[eluser]Unknown[/eluser]
so straight to the point, im upgrading my website from 1.7.2. core to 2.0.2. core
everything works just fine, except when i press the login button or any button that has anything to do with administration process, like delete, add, etc there is an error message

Severity: Notice

Message: Undefined property: Dashboard::$_admin_view

Filename: admin/dashboard.php

Line Number: 16
An Error Was Encountered

Unable to load the requested file: .php

im following the upgrading user guide as best as i can
anybody have the solution?

[eluser]NeoArc[/eluser]
Are you using Backendpro? Codeigniter by default does not have an administrator panel

[eluser]Aken[/eluser]
Look at that line of code, figure out what it's supposed to do, then find out where that variable is getting set and why it's not now.