Access admin page doesn't work

Hi!

I' m changing the theme of nopcommerce and, when I click on the admin link, doesn't work.
The error is:

Page not found
The page you requested was not found, and we have a fine guess why.
If you typed the URL directly, please make sure the spelling is correct.
The page no longer exists. In this case, we profusely apologize for the inconvenience and for any damage this may cause.

Can anybody help me please?!!

Thanks!

Enure that Nop.Admin project is re-built and Nop.Admin.dll file exists in the \bin directory

Hi!

Thank you very much! Its works like a charm.