My question is will SQLEXPRESS work in both SQL and Windows authentication modes? I believe the answer is no, but I am not sure.

We have a commercial application that will only work with SQL authentication. We already have a SQLEXPRESS 2008 server, but it is set up for Windows authentication. If I create a user with SQL authentication and try to log in, the Application log says 

```
Login failed for user 'cnorton'. 
Reason: An attempt to login using SQL authentication failed. 
Server is configured for Windows authentication only. 
[CLIENT: 10.100.100.30]

```

So, do I need to deploy a separate SQLEXPRESS server, or are there settings unknown to me right now, that would allow both authentication modes?

Thanks.