Q: How do I get my mail sent to the correct mailbox on my H: drive and move all of my messages over to it:?
A:

With Outlook open, go to File--> Open --> Personal Folders File (.pst).

Browse to your mailbox at H:\Mail\mailbox.pst. Click on "yes" to copy shortcuts to the new folder. A second Personal Folders File will open in your Folder List .

Note: If you don't have a Folder List on your screen, go to View and click "Folder List"]

Right-click on this newly added folder in the Folder List ("CorrectMailbox" in above picture) and click Properties. On the Properties Window, click the box next to "Deliver POP mail to this personal folders file" and click OK.

Note: If you would like to change the name for this Mailbox Folder that shows up in your Folder List, click Advanced and change the Name field.

You will get a message saying that this change won't take effect until you close Outlook. CLOSE Outlook and open it up again.

If you previously downloaded mail to the incorrect mailbox, you can move the mail messages from the incorrect mailbox to the correct mailbox (the one you just opened on your H: drive) by dragging and dropping the mail from one Inbox to another them.

When you are done with moving all mail from the incorrect/old mailbox, close it by right-clicking on it and clicking "Close Mailbox" (In picture below, it is called "Incorrect Mailbox")