BinaryFormatter deserialization failure

Hi,
I have seen similar post on this topic but I need more detailed help so
I posted it again.

In my application, I use BinaryFormatter to serialize/deserialize my
data. Recently, I added new properties in my serializable class and
since then I can't deserialize my preexisting data. The exception
that I got is "BinaryFormatter Version incompatibility. Expected
Version 1.0. Received Version 49.0." and the exception source is
mscorlib. What should I do in this case? I'm just clueless.
I would appreciate any help.

Thank you.

Sung.