How to merge two archive files in Microsoft Outlook

If you have multiple archive files or .pst files you want to merge the steps below should help you resolve that issue.  Before going any further creating backups is always a good idea in the event anything happens!

  1. Open both Archive/.pst files in Outlook, if you are not sure how to do that click here for instructions on that
  2. Expand both archives on the left pane of Outlook
  3. Go to the inbox of the archive/.pst you want to merge from and select all your emails from the inbox by pressing Ctrl+A
  4. Drag and drop the emails from that archive/.pst into the archive/.pst file you want to keep
  5. Repeat steps 3 and 4 for each folder in the old archive/.pst file

I hope this works for you.  This is the same method I used to merge my old .pst file in Outlook.