>Is your underlying oFileStream doing something that you can't just use File.Copy?

I need to concatenate files.

>What do you get for the lengths for the following:

I get the same value as before. The problem is with the streaming approach. On certain files, and this happens very rare, it just doesn't work. I found a new approach which is finally giving me the right amount of bytes for the first file. I will class it and see if the end result is ok.