Here is information from http://www.insideoe.com/files/store.htm. Note
that it says below that a DBX folder should be limited to 2MB. 2MB??? I
get messages with attachments larger than 2MB. Are a couple of zeros
missing below?

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name.dbx

This represents a user-created mail folder and its messages. The number
of folders is limited only by your disk space, but don't let any one
folder grow above 2Mb or so or performance is likely to suffer.
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