# Compiler Error ASPIRE007

<Badge
  text="Version introduced: 9.0.0"
  variant="note"
  size="large"
  class:list={'mb-1'}
/>

> The project is missing a required Aspire.AppHost.Sdk with a version of at least 9.0.0. Please add the following line after the Project declaration `<Sdk Name="Aspire.AppHost.Sdk" Version="9.0.0" />`.

The Aspire AppHost package references require Aspire SDK version 9.0.0 or greater. The SDK reference is either being omitted or is using a version older than 9.0.0.

## To correct this error

Update the referenced SDK version to 9.0.0 or the latest.

If the SDK reference is missing from your project file, add it, as demonstrated in the following snippet:

```xml title="C# project file"
<Project Sdk="Microsoft.NET.Sdk">

  <Sdk Name="Aspire.AppHost.Sdk" Version="9.0.0" />

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net9.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
    <IsAspireHost>true</IsAspireHost>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Aspire.Hosting.AppHost" Version="9.2.0" />
  </ItemGroup>

</Project>
```