If you're ever confronted with IIS error "500.19", it's because the .net AppPool for PhoenixSQL isn't set correctly. The steps below will show you how we can correct that.
1. Click on your Windows Start Button and search 'IIS'
2. Select 'Internet Information Services (IIS) Manager'
3. Expand your machine name on the left side of the IIS Manager
4. Expand 'Sites'
5. Expand 'Default Web Site'
6. Select 'PhoenixSQL'
7. Select 'Basic Settings' under 'Actions' on the right side of IIS Manager
8. Click the 'Select' button
9. Click the drop down menu for the application pool selection and select 'Classic .NET AppPool'
10. Confirm the properties say .Net Framework Version: 2.0 and Pipeline mode: Classic then press OK
11. Repeat steps 6 - 10 for 'PhoenixSQLWebservice_x64', 'PSQLWCFService', and 'TerminalWindowWebSetup'