I'm having some trouble with the portable_binary_archive. When we serialze our classes via the text archive, they go in and out just fine. My simple test cases work great with the portable_binary_archive. However, in our production code, I get an input stream error exception tossed when I try to read a class that has STL elements in it. I have tried reordering includes and making sure the boost/serialization/list.hpp or whatever comes in front of the STL list class. Heck, I even put all those includes as the very 1st line of my test program to make sure they were included 1st. I am at a loss as the exception really doesn't tell me much, and the only thing I could figure out is that reordering the includes did in fact fix a few of these exceptions. (I still have one left... very annoying) Any ideas? I'd post the code, but it is very intertwined and difficult to distill a clean example. (and my stupid trail test does in fact work) Larry