diff --git a/src/OpenIddict.Core/OpenIddictBuilder.cs b/src/OpenIddict.Core/OpenIddictBuilder.cs
index f21bd78f..19324381 100644
--- a/src/OpenIddict.Core/OpenIddictBuilder.cs
+++ b/src/OpenIddict.Core/OpenIddictBuilder.cs
@@ -240,7 +240,7 @@ namespace Microsoft.AspNetCore.Builder {
/// The type of the custom store.
/// The .
public virtual OpenIddictBuilder AddUserStore() {
- var contract = typeof(IOpenIddictTokenStore<>).MakeGenericType(UserType);
+ var contract = typeof(IOpenIddictUserStore<>).MakeGenericType(UserType);
if (!contract.IsAssignableFrom(typeof(TStore))) {
throw new InvalidOperationException("Custom stores must implement IOpenIddictUserStore.");
}