Sorry, It's like mokwit is saying. The folder needs to be compressed. Are you using WinXp? On the system I'm on now, there is a compression tool when using the right mouse button. Right-click the folder, click 'send to' and see if you can find it. It doesn't really appear to change the actual size of the file but it modifies it so that the system recognizes it as a 'zipped' file.
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