Navigate to page with content displays page not found error I have a URL (/url1) that I navigate to that is showing content because of the Context module. 

The Context module has a condition that when the user navigates to /url1, some view blocks are rendered on the page. However, it is also rendering a "Page not found" error at the bottom of the page. 

I can't figure out how to remove that message and get it to work properly. It even has the title "Page not found" on the tab with the page. The blocks render just fine in the way I want them.
You need to have some sort of content assigned to the URL url1. The simplest way would be to create a new Basic page node and set its URL alias field to url1.

By the way, what you are seeing now is the "page that is displayed when no other content matches the requested document" (Administration &gt;&gt; Configuration &gt;&gt; System &gt;&gt; Site Information &gt;&gt; Default 404 (not found) page). You can have a specific page assigned as your Page not found page, or Drupal will build the content for it on the fly, and show it using the most appropriate template in your theme (most likely page.tpl.php).