Some folks have had trouble with FreeTextBox under dasBlog not working. The symptom is that the FreeTextBox won't render at all. There's no error and no idea why. It's very frustrating. While we're working on the "no error" issue, the underlying problem isn't dasBlog.

DasBlog builds with a reference to the strongly-typed FreeTextBox 3.0.5000.1. However, you may have 3.0.5000.3. Or, like me, downloaded and installed the latest 3.0.5000.5.

You need to tell .NET that you know what you're doing and say "when you ask for this version, please bind to that version." 

So, added to the web.config of my dasBlog:

<runtime>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
        <dependentAssembly>  
            <assemblyIdentity name="FreeTextBox" publicKeyToken="5962a4e684a48b87" culture="neutral"/> 
                <bindingRedirect oldVersion="3.0.0.0-3.0.5000.4" newVersion="3.0.5000.5" /> 
        </dependentAssembly>
    </assemblyBinding>
</runtime>

And everything works great. I suggest you do this if you've updated FreeTextBox. Note also that this is needed regardless of whether FreeTextBox is in the GAC or not.