Here is my advice: you should seriously consider archiving (parts of) your data into XML, with where needed, additional native file such as TIFF, MSG, XLS or Word to conserve the original file system in a (low cost) file system. Examples of description of such format specifications can be found here:http://www.zylab.com/Technology/xml_storage.html.
This approach is especially beneficial for the “write-once read-many” type of data such as email, archived (SharePoint) projects, customer records, legal agreements, data and files from former employees, and other data that will no longer change, but that needs to remain accessible for a defined period of time as part of compliance policies.
Here are a number of additional benefits of the XML approach:
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