diff --git a/source/poodinis/container.d b/source/poodinis/container.d
index cf9b85e..383e01f 100644
--- a/source/poodinis/container.d
+++ b/source/poodinis/container.d
@@ -1,6 +1,7 @@
 module poodinis.container;
 
 import std.string;
+import std.array;
 
 struct Registration {
 	TypeInfo registeredType = null;
@@ -17,6 +18,12 @@ class RegistrationException : Exception {
 	}
 }
 
+class ResolveException : Exception {
+	this(string message, TypeInfo resolveType) {
+		super(format("Exception while resolving type %s: %s", resolveType.toString(), message));
+	}
+}
+
 class Container {
 	
 	private static Registration[TypeInfo] registrations;
@@ -44,12 +51,21 @@ class Container {
 	private static void checkValidity(InterfaceType)(TypeInfo registeredType, TypeInfo_Class instanceType) {
 		InterfaceType instanceCanBeCastToInterface = cast(InterfaceType) instanceType.create(); 
 		if (!instanceCanBeCastToInterface) {
-			string errorMessage = format("%s cannot be cast to %s", instanceType.name, registeredType.toString());
+			string errorMessage = format("%s cannot be cast to %s.", instanceType.name, registeredType.toString());
 			throw new RegistrationException(errorMessage, registeredType, instanceType);
 		}
 	}
 	
 	public static ClassType resolve(ClassType)() {
-		return cast(ClassType) registrations[typeid(ClassType)].getInstance();
+		TypeInfo resolveType = typeid(ClassType);
+		Registration* registration = resolveType in registrations;
+		if (!registration) {
+			throw new ResolveException("Type not registered.", resolveType);
+		}
+		return cast(ClassType) registration.getInstance();
+	}
+	
+	public static void clearRegistrations() {
+		registrations.clear();
 	}
 }
diff --git a/test/poodinis/containertest.d b/test/poodinis/containertest.d
index 19242aa..829b4ed 100644
--- a/test/poodinis/containertest.d
+++ b/test/poodinis/containertest.d
@@ -14,12 +14,14 @@ version(unittest) {
 	
 	unittest {
 		// Test register concrete type
+		Container.clearRegistrations();
 		auto registration = Container.register!(TestClass)();
 		assert(registration.registeredType == typeid(TestClass), "Type of registered type not the same");
 	}
 	
 	unittest {
 		// Test resolve registered type
+		Container.clearRegistrations();
 		Container.register!(TestClass)();
 		TestClass actualInstance = Container.resolve!(TestClass)();
 		assert(actualInstance !is null, "Resolved type is null");
@@ -28,6 +30,7 @@ version(unittest) {
 	
 	unittest {
 		// Test register interface
+		Container.clearRegistrations();
 		Container.register!(TestInterface, TestClass)();
 		TestInterface actualInstance = Container.resolve!(TestInterface)();
 		assert(actualInstance !is null, "Resolved type is null");
@@ -36,12 +39,20 @@ version(unittest) {
 	
 	unittest {
 		// Test register unrelated types fails
+		Container.clearRegistrations();
 		assertThrown!RegistrationException(Container.register!(UnrelatedClass, TestClass)(), "Registering unrelated types does not fail");
 	}
 	
 	unittest {
 		// Test register unrelated types with disabled check on registration
+		Container.clearRegistrations();
 		assertNotThrown!RegistrationException(Container.register!(UnrelatedClass, TestClass)(false), "Registering unrelated types while disabling type validity fails");
 	}
 	
+	unittest {
+		// Test resolve non-registered type
+		Container.clearRegistrations();
+		assertThrown!ResolveException(Container.resolve!(TestClass)(), "Resolving non-registered type does not fail");
+	}
+	
 }
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