-26 Corlib compilation is not supported in MS.NET
+-27 Attribute resolved to two different types
+
----------
Errors that we have allocated that will have corresponding errors in
-217 Wrong number of type parameters
-218 Invalid constraints clause
+
+-219 Type argument doesn't meet constraints.
+
+-220 Cannot resolve constructed type
+
+-221 params modifier present in anonymous method declaration
+
+-222 yield statement only available in C# 2.0 mode