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MS Outlook 2010 users should also be aware that .pst files should not exceed 2GB in size. If your email archives are becoming too large you should break them up to keep these pst files under 2GB. Some instructions from Microsoft on how to manually manage this can be found here:
http://office.microsoft.com/en-us/outlook-help/archive-items-manually-HA010355564.aspx
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