Hi Sarah,
Do you know what database you are using? If you're not using SQLite (and if you don't know what it is you probably aren't using it), then you can try commenting out that part of Web.config. Its near the bottom of the Web.config file, it looks like this:
<add name="subsonicSQLite" type="SubSonic.SQLiteMonoDataProvider, SubSonic"
connectionStringName="Subsonic-SQLite"
generatedNamespace="mojoPortal.Data.Common"
stripTableText="mp_,ws_"
removeUnderscores="true"
useSPs="false"
/>
You can comment it out by wrapping it with <!-- --> like this:
<!--
<add name="subsonicSQLite" type="SubSonic.SQLiteMonoDataProvider, SubSonic"
connectionStringName="Subsonic-SQLite"
generatedNamespace="mojoPortal.Data.Common"
stripTableText="mp_,ws_"
removeUnderscores="true"
useSPs="false"
/>
-->
Hope it helps,
Joe