Nop2.3 installation Error

Copied no source v2.3 and extracted to server entered database info and clicked install.
Cant work out why it is failing.
Below is the errror I receive:

•Setup failed: System.InvalidOperationException: Sequence contains more than one element at System.Linq.Enumerable.Single[TSource](IEnumerable`1 source) at System.Linq.Queryable.Single[TSource](IQueryable`1 source) at Nop.Services.Installation.InstallationService.InstallSettings() in f:\Own\NopCommerce\Sources\src\Libraries\Nop.Services\Installation\InstallationService.cs:line 4531 at Nop.Services.Installation.InstallationService.InstallData(String defaultUserEmail, String defaultUserPassword, Boolean installSampleData) in f:\Own\NopCommerce\Sources\src\Libraries\Nop.Services\Installation\InstallationService.cs:line 9392 at Nop.Web.Controllers.InstallController.Index(InstallModel model) in f:\Own\NopCommerce\Sources\src\Presentation\Nop.Web\Controllers\InstallController.cs:line 435

Any help would be appreciated.

https://www.nopcommerce.com/boards/t/10620/200-beta-install-error-new-rev-existing-db.aspx

I have few issues with the migration too

1. Manage Categories
My original categories doesn't work anymore. When I click on the main categories in the admin panel I have pahe not found
I stop and restard the webstite and still doeant work. I clear the server Cache and I restarted the app and same problem

2. Topis listed in double
I havethe topics listed in double. As per exemple, About us is my text and under it I have listed a second about us with the nop defaut text.

3. Again in the categories I have my old images

So I don't know what to do anymore any ideas ?

thanks

Yves