Why Does the converted PST file is smaller in size compared to source NSF file?

Have You "I have purchased the Full version of Export Notes software & successfully converted my 4 GB NSF file to PST files, but the file size of resulting PST file is 900 MB, Why there is so huge difference in converted file size?"type of error? Solve Here.

This is the common query asked by most of the users of Export Notes or Notes Address Book Converter. So as to resolve this common query, please read the explanation stated below:

There are few reasons for the difference in the converted PST file size and the source NSF file as follows:

An empty NSF file size is around 13 MB (you can check this by creating new nsf file) whereas an empty pst size is 256 KB.

There is a difference in storage format of both the files (NSF file retains more email meta data as compared to PST file email metada).

Actual data present in the NSF file is less as compared to the size of the NSF. So resulting pst will be smaller in size as compared to source NSF file. To check this -

Create copy of existing NSF file
Delete few folders or emails from that NSF file
Check the resulting file size of the NSF file, you will see no change in file size. Seems strange !

Delete all emails/folders from the NSF file and still you see no change in file size, this means even though there is no data in NSF file but the NSF file still retains the same file size.)

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