Although this back-and-forth copying will solve your problem, it's a major-league pain in the hindquarters. And it's prone to error as well -- you may accidentally overwrite a newer .pst file with an older one.
If you're willing to spend a little money, there's a more bulletproof solution: Get a program that will automatically synchronize your Outlook data between PCs. I found two good pieces of software that do the trick.
SynchPST for Outlook and PSTSync both do similar tasks and come with extras, like the ability to copy and synchronize only individual folders instead of entire .pst files. They're both shareware, so you can try them before you buy them. SynchPST costs US$39.95 for the Basic version and US$69.95 for the Professional version, which has extras such as the ability to schedule automated syncs. PSTSync costs US$59.99.
If you use a laptop and a desktop, and have set up your desktop for remote access, then there's an even simpler solution. When you're on the road and need to check your e-mail, make a remote connection to your desktop and run Outlook remotely. That way, you won't need to do any synchronization at all.
Annoyance No. 9
People complain my e-mails have weird characters and spaces in them. Outlook 2007 uses Microsoft Word as its mail editor. Even if you don't have Word installed on your system, Outlook uses a Word .dll, and so Word is what you get when you compose mail. Because of that, when you type an apostrophe, quotation mark or some other special characters, they may show up in other people's e-mail as blank spaces or oddball characters.
How to fix it: The problems are caused by Word's use of so-called smart quotes, which from some points of view aren't so smart. They're not plain-text characters, and so other e-mail readers may interpret them oddly, particularly if the e-mail reader uses plain text instead of HTML.
To fix the problem most easily, in Outlook select Tools -- Options -- Mail Format, and from the drop-down box in the Message format area, choose Plain text and click OK. From now on, Outlook won't use smart quotes. However, it also won't use HTML, either, so you won't be able to use fonts, colors and so on.
If you'd prefer to use HTML text for most messages but use plain text only for some, when you create an e-mail message, select Options from the ribbon at the top of Outlook, and click Plain Text. That way, only that message will be created using plain text; all others will still use HTML.