Compiler Error CS0463
Evaluation of the decimal constant expression failed with error: 'error'
This errors occurs when a constant decimal expression overflows at compile time.
Typically you get overflow errors at run time. In this case, you defined the constant expression in such a way that the compiler could evaluate the result and know that an overflow would happen.
Example
The following code generates error CS0463.
// CS0463.cs
using System;
class MyClass
{
public static void Main()
{
const decimal myDec = 79000000000000000000000000000.0m + 79000000000000000000000000000.0m; // CS0463
Console.WriteLine(myDec.ToString());
}
}