diff --git a/src/main/scala/li/cil/oc/integration/opencomputers/DriverCPU.scala b/src/main/scala/li/cil/oc/integration/opencomputers/DriverCPU.scala
index 81655f760..df3cdd997 100644
--- a/src/main/scala/li/cil/oc/integration/opencomputers/DriverCPU.scala
+++ b/src/main/scala/li/cil/oc/integration/opencomputers/DriverCPU.scala
@@ -12,6 +12,7 @@ import li.cil.oc.common.Slot
 import li.cil.oc.common.Tier
 import li.cil.oc.common.item
 import li.cil.oc.common.item.Delegator
+import li.cil.oc.server.machine.luac.NativeLuaArchitecture
 import net.minecraft.item.ItemStack
 
 import scala.collection.convert.WrapAsScala._
@@ -40,7 +41,13 @@ abstract class DriverCPU extends Item with Processor {
 
   override def architecture(stack: ItemStack): Class[_ <: Architecture] = {
     if (stack.hasTagCompound) {
-      val archClass = stack.getTagCompound.getString(Settings.namespace + "archClass")
+      val archClass = stack.getTagCompound.getString(Settings.namespace + "archClass") match {
+        case clazz if clazz == classOf[NativeLuaArchitecture].getName =>
+          // Migrate old saved CPUs to new versions (since the class they refer still
+          // exists, but is abstract, which would lead to issues).
+          api.Machine.LuaArchitecture.getName
+        case clazz => clazz
+      }
       if (!archClass.isEmpty) try return Class.forName(archClass).asSubclass(classOf[Architecture]) catch {
         case t: Throwable =>
           OpenComputers.log.warn("Failed getting class for CPU architecture. Resetting CPU to use the default.", t)
diff --git a/src/main/scala/li/cil/oc/server/machine/Machine.scala b/src/main/scala/li/cil/oc/server/machine/Machine.scala
index d4cff5c12..8bb64559b 100644
--- a/src/main/scala/li/cil/oc/server/machine/Machine.scala
+++ b/src/main/scala/li/cil/oc/server/machine/Machine.scala
@@ -124,9 +124,12 @@ class Machine(val host: MachineHost) extends prefab.ManagedEnvironment with mach
         case Some(driver: Processor) if driver.slot(stack) == Slot.CPU =>
           Option(driver.architecture(stack)) match {
             case Some(clazz) =>
-              if (architecture == null || architecture.getClass != clazz) {
+              if (architecture == null || architecture.getClass != clazz) try {
                 newArchitecture = clazz.getConstructor(classOf[machine.Machine]).newInstance(this)
               }
+              catch {
+                case t: Throwable => OpenComputers.log.warn("Failed instantiating a CPU architecture.", t)
+              }
               else {
                 newArchitecture = architecture
               }