Presumably you have all your POP accounts sharing one set of folders, which I seem to recall was the default for 2007? It has since changed.

For separate files you need to create new databases for each account. You can do that from Account Settings > E-mail > Select the account from the list > Change Folder > New Outlook Data File - give it a name that reflects the content.

Repeat for each relevant address.

If you setup your accounts as IMAP separate folders are created automatically.

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Graham Mayor - MS MVP (Word) (2002-2019)
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