# System.Configuration

``` diff
 namespace System.Configuration {
     public class ConfigurationErrorsException : ConfigurationException {
-        protected ConfigurationErrorsException(SerializationInfo info, StreamingContext context);
+        [EditorBrowsableAttribute(1)]
+        [ObsoleteAttribute("This API supports obsolete formatter-based serialization. It should not be called or extended by application code.", DiagnosticId="SYSLIB0051", UrlFormat="https://aka.ms/dotnet-warnings/{0}")]
+        protected ConfigurationErrorsException(SerializationInfo info, StreamingContext context);
-        public override void GetObjectData(SerializationInfo info, StreamingContext context);
+        [EditorBrowsableAttribute(1)]
+        [ObsoleteAttribute("This API supports obsolete formatter-based serialization. It should not be called or extended by application code.", DiagnosticId="SYSLIB0051", UrlFormat="https://aka.ms/dotnet-warnings/{0}")]
+        public override void GetObjectData(SerializationInfo info, StreamingContext context);
     }
     public class ConfigurationException : SystemException {
-        protected ConfigurationException(SerializationInfo info, StreamingContext context);
+        [EditorBrowsableAttribute(1)]
+        [ObsoleteAttribute("This API supports obsolete formatter-based serialization. It should not be called or extended by application code.", DiagnosticId="SYSLIB0051", UrlFormat="https://aka.ms/dotnet-warnings/{0}")]
+        protected ConfigurationException(SerializationInfo info, StreamingContext context);
-        public override void GetObjectData(SerializationInfo info, StreamingContext context);
+        [EditorBrowsableAttribute(1)]
+        [ObsoleteAttribute("This API supports obsolete formatter-based serialization. It should not be called or extended by application code.", DiagnosticId="SYSLIB0051", UrlFormat="https://aka.ms/dotnet-warnings/{0}")]
+        public override void GetObjectData(SerializationInfo info, StreamingContext context);
     }
     public sealed class ConfigurationSectionCollection : NameObjectCollectionBase {
-        public override void GetObjectData(SerializationInfo info, StreamingContext context);
+        [EditorBrowsableAttribute(1)]
+        [ObsoleteAttribute("This API supports obsolete formatter-based serialization. It should not be called or extended by application code.", DiagnosticId="SYSLIB0051", UrlFormat="https://aka.ms/dotnet-warnings/{0}")]
+        public override void GetObjectData(SerializationInfo info, StreamingContext context);
     }
     public sealed class ConfigurationSectionGroupCollection : NameObjectCollectionBase {
-        public override void GetObjectData(SerializationInfo info, StreamingContext context);
+        [EditorBrowsableAttribute(1)]
+        [ObsoleteAttribute("This API supports obsolete formatter-based serialization. It should not be called or extended by application code.", DiagnosticId="SYSLIB0051", UrlFormat="https://aka.ms/dotnet-warnings/{0}")]
+        public override void GetObjectData(SerializationInfo info, StreamingContext context);
     }
     public sealed class PropertyInformationCollection : NameObjectCollectionBase {
-        public override void GetObjectData(SerializationInfo info, StreamingContext context);
+        [EditorBrowsableAttribute(1)]
+        [ObsoleteAttribute("This API supports obsolete formatter-based serialization. It should not be called or extended by application code.", DiagnosticId="SYSLIB0051", UrlFormat="https://aka.ms/dotnet-warnings/{0}")]
+        public override void GetObjectData(SerializationInfo info, StreamingContext context);
     }
     public class SettingsPropertyIsReadOnlyException : Exception {
-        protected SettingsPropertyIsReadOnlyException(SerializationInfo info, StreamingContext context);
+        [EditorBrowsableAttribute(1)]
+        [ObsoleteAttribute("This API supports obsolete formatter-based serialization. It should not be called or extended by application code.", DiagnosticId="SYSLIB0051", UrlFormat="https://aka.ms/dotnet-warnings/{0}")]
+        protected SettingsPropertyIsReadOnlyException(SerializationInfo info, StreamingContext context);
     }
     public class SettingsPropertyNotFoundException : Exception {
-        protected SettingsPropertyNotFoundException(SerializationInfo info, StreamingContext context);
+        [EditorBrowsableAttribute(1)]
+        [ObsoleteAttribute("This API supports obsolete formatter-based serialization. It should not be called or extended by application code.", DiagnosticId="SYSLIB0051", UrlFormat="https://aka.ms/dotnet-warnings/{0}")]
+        protected SettingsPropertyNotFoundException(SerializationInfo info, StreamingContext context);
     }
     public class SettingsPropertyWrongTypeException : Exception {
-        protected SettingsPropertyWrongTypeException(SerializationInfo info, StreamingContext context);
+        [EditorBrowsableAttribute(1)]
+        [ObsoleteAttribute("This API supports obsolete formatter-based serialization. It should not be called or extended by application code.", DiagnosticId="SYSLIB0051", UrlFormat="https://aka.ms/dotnet-warnings/{0}")]
+        protected SettingsPropertyWrongTypeException(SerializationInfo info, StreamingContext context);
     }
 }
```

