Nat.li

Add to App.config :

<system.data>
    <DbProviderFactories>
     <remove invariant="System.Data.SQLite"/>
      <add name="SQLite Data Provider" invariant="System.Data.SQLite" description=".Net Framework Data   Provider for SQLite"
      type="System.Data.SQLite.SQLiteFactory, System.Data.SQLite" />
     </DbProviderFactories>
  </system.data>

Here’s my full config:

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <startup useLegacyV2RuntimeActivationPolicy="true">
    <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0" />
    <requiredRuntime version="v4.0.20506" />
  </startup>
  <system.data>
    <DbProviderFactories>
      <remove invariant="System.Data.SQLite" />
      <add name="SQLite Data Provider" invariant="System.Data.SQLite" description=".Net Framework Data   Provider for SQLite" type="System.Data.SQLite.SQLiteFactory, System.Data.SQLite" />
    </DbProviderFactories>
  </system.data>
  <connectionStrings>
    <add name="Connection1" connectionString="data source=database.db;version=3;useutf8encoding=True" providerName="System.Data.SQLite" />
  </connectionStrings>
</configuration>

Other things to check:

-That you are actually referencing the required libraries
-That said libraries are set to “Copy Local” (defaults to False for me!)