I have downloaded subtext to try out this blog software. After I unzip it, I double click SubtextSolution.sln to open the solution. When I run it, I got an error mesg saying,

A project with an Output Type of Class Library cannot be started directly.

In order to debug this project, add an executable project to this solution which references the library project. Set the executable project as the startup project.

How do I run this subtext software? Thanks.

Activate the Web Project and run again, or you can set the Web Project in the Solution as the Startup-Project. So das the right project ist startetd.

Sorry I don't know what you meant. But I did something though not sure if I'm doing right. What I did is after I open .sln, I go to "Solution Explorer" and then right click the solution 'SubtextSolution'. Then I change the radio button from "Current selection" to "Single startup project" and then select Subtext.web 

When that I run it, but still got error: 

An exception of type 'System.Data.SqlClient.SqlException' occurred in Subtext.Installation.DLL but was not handled in user code

Additional information: Cannot open database "SubtextData_1.9" requested by the login. The login failed.
Login failed for user 'MOL-B123CF732AA\molweb96'.

Anyway, it's ok. I think I will give up this subtext at the moment. Right now, I'm trying out CommunityServer and managed to get it working.