Hi, I'm trying to use the serialization library and was having a compile error using MSVC 2005. So I decided to try and compile "A Very Simple Case" from the tutorial, and that of course works. But then I noticed that the example serializes a const object, that sort of is rather useless, so I removed the const specifier, and I got the same error that I was getting with my program, namely: warning C4099: 'boost::serialization::static_warning_impl<false>::STATIC_WARNING' : type name first seen using 'struct' now seen using 'class' I went googling for an answer and I found that I should look at the rationale on the docs, but the rationale (http://www.boost.org/doc/libs/1_47_0/libs/serialization/doc/rationale.html) doesn't seem at all relevant. I finally sort of guessed that I wanted was probably to modify the tracking behavior on my program (looking at the thread http://lists.boost.org/boost-users/2010/05/59107.php ). But my objects are not on the stack, so I'm not really sure. My class structure is a bit more complicated than the simple example, but my question basically is, what changes would be appropriate on the simple example so that it would compile for non-const objects? Thanks