diff --git a/OSLC4Net_SDK/OSLC4Net.Core/Model/OccursExtension.cs b/OSLC4Net_SDK/OSLC4Net.Core/Model/OccursExtension.cs
index b45d88a5..ad7c89ff 100644
--- a/OSLC4Net_SDK/OSLC4Net.Core/Model/OccursExtension.cs
+++ b/OSLC4Net_SDK/OSLC4Net.Core/Model/OccursExtension.cs
@@ -32,7 +32,7 @@ public static Occurs FromString(string value)
             }
         }
 
-        throw new ArgumentException();
+        throw new ArgumentException($"Invalid string representation of Occurs value: {value}", nameof(value));
     }
 
     public static Occurs FromURI(URI uri)
diff --git a/OSLC4Net_SDK/OSLC4Net.Core/Model/RepresentationExtension.cs b/OSLC4Net_SDK/OSLC4Net.Core/Model/RepresentationExtension.cs
index d83f2b56..e1e83629 100644
--- a/OSLC4Net_SDK/OSLC4Net.Core/Model/RepresentationExtension.cs
+++ b/OSLC4Net_SDK/OSLC4Net.Core/Model/RepresentationExtension.cs
@@ -32,7 +32,7 @@ public static Representation FromString(string value)
             }
         }
 
-        throw new ArgumentException();
+        throw new ArgumentException($"Invalid string representation of Representation value: {value}", nameof(value));
     }
 
     public static Representation FromURI(URI uri)
diff --git a/OSLC4Net_SDK/OSLC4Net.Server.Providers/OslcRdfInputFormatter.cs b/OSLC4Net_SDK/OSLC4Net.Server.Providers/OslcRdfInputFormatter.cs
index 92fece80..5699341a 100644
--- a/OSLC4Net_SDK/OSLC4Net.Server.Providers/OslcRdfInputFormatter.cs
+++ b/OSLC4Net_SDK/OSLC4Net.Server.Providers/OslcRdfInputFormatter.cs
@@ -48,8 +48,7 @@ public override async Task<InputFormatterResult> ReadRequestBodyAsync(
             OslcMediaType.TEXT_TURTLE => RdfFormat.Turtle,
             OslcMediaType.APPLICATION_NTRIPLES => RdfFormat.NTriples,
             OslcMediaType.APPLICATION_JSON_LD => RdfFormat.JsonLd,
-            _ => throw new ArgumentOutOfRangeException(nameof(requestedType),
-                "Unknown RDF format"),
+            _ => throw new NotSupportedException($"Unknown RDF format: {requestedType}"),
         };
         using var reader = new StreamReader(context.HttpContext.Request.Body, encoding);
 
diff --git a/OSLC4Net_SDK/OSLC4Net.Server.Providers/OslcRdfOutputFormatter.cs b/OSLC4Net_SDK/OSLC4Net.Server.Providers/OslcRdfOutputFormatter.cs
index a6cfbb14..159bdc73 100644
--- a/OSLC4Net_SDK/OSLC4Net.Server.Providers/OslcRdfOutputFormatter.cs
+++ b/OSLC4Net_SDK/OSLC4Net.Server.Providers/OslcRdfOutputFormatter.cs
@@ -61,8 +61,7 @@ public override async Task WriteResponseBodyAsync(OutputFormatterWriteContext co
                 OslcMediaType.TEXT_TURTLE => RdfFormat.Turtle,
                 OslcMediaType.APPLICATION_NTRIPLES => RdfFormat.NTriples,
                 OslcMediaType.APPLICATION_JSON_LD => RdfFormat.JsonLd,
-                _ => throw new ArgumentOutOfRangeException(nameof(requestedType),
-                    "Unknown RDF format"),
+                _ => throw new NotSupportedException($"Unknown RDF format: {requestedType}"),
             },
             Graph = graph
         };