diff --git a/plugins/UM3NetworkPrinting/src/Models.py b/plugins/UM3NetworkPrinting/src/Models.py
index e2ad411e90..d0708c8127 100644
--- a/plugins/UM3NetworkPrinting/src/Models.py
+++ b/plugins/UM3NetworkPrinting/src/Models.py
@@ -6,6 +6,10 @@
 class BaseModel:
     def __init__(self, **kwargs):
         self.__dict__.update(kwargs)
+        self.validate()
+
+    def validate(self):
+        pass
 
 
 ##  Class representing a material that was fetched from the cluster API.
@@ -19,6 +23,10 @@ class ClusterMaterial(BaseModel):
         self.density = None  # type: str
         super().__init__(**kwargs)
 
+    def validate(self):
+        if not self.guid:
+            raise ValueError("guid is required on ClusterMaterial")
+
 
 ##  Class representing a local material that was fetched from the container registry.
 class LocalMaterial(BaseModel):
@@ -40,3 +48,9 @@ class LocalMaterial(BaseModel):
         self.definition = None  # type: str
         self.compatible = None  # type: bool
         super().__init__(**kwargs)
+
+    def validate(self):
+        if not self.GUID:
+            raise ValueError("guid is required on LocalMaterial")
+        if not self.id:
+            raise ValueError("id is required on LocalMaterial")
diff --git a/plugins/UM3NetworkPrinting/src/SendMaterialJob.py b/plugins/UM3NetworkPrinting/src/SendMaterialJob.py
index 48760af28e..6f33e75ee1 100644
--- a/plugins/UM3NetworkPrinting/src/SendMaterialJob.py
+++ b/plugins/UM3NetworkPrinting/src/SendMaterialJob.py
@@ -159,8 +159,8 @@ class SendMaterialJob(Job):
             Logger.log("e", "Request material storage on printer: I didn't understand the printer's answer.")
         except json.JSONDecodeError:
             Logger.log("e", "Request material storage on printer: I didn't understand the printer's answer.")
-        except TypeError:
-            Logger.log("e", "Request material storage on printer: Printer's answer was missing GUIDs.")
+        except ValueError:
+            Logger.log("e", "Request material storage on printer: Printer's answer was missing a value.")
 
     ##  Retrieves a list of local materials
     #