Moving the AutoCorrect entries you created in Word from one PC to another is not nearly as easy as such a common operation should be, but it is possible.
Back in May 2008, I described a macro that made it easy to copy custom AutoCorrect entries from a version of Microsoft Word on one PC to a Word installation on another machine. Unfortunately, the macro, written by Microsoft MVP Dave Rado, is no longer available.
I take no pleasure in criticizing Microsoft's inability to meet the needs of its customers, but some of us have been using Word for close to 20 years. Shouldn't we be able to transfer our handcrafted AutoCorrect entries and other customizations between PCs without having to drag system files between folders that would be a challenge to find even if their location didn't change with every new version of Word?
But no. If you want to import your AutoCorrect and AutoText entries, macros, and other Word customizations, you have to close Word and all other Office programs, root around in system folders to find and copy specific files, and then paste the files into the equivalent folders on the destination PC.
Microsoft provides instructions for moving your custom AutoCorrect entries between Word 2007 installations in Knowledge Base article 926927. Those instructions should also apply to Word 2010. KB article 826147 on the Microsoft Support site describes the same process for Word 2003.
Word 2007 introduced Building Blocks, which complicate migration of customizations from previous versions. Microsoft's TechNet site offers an overview of Office 2007 migration. Much of this information applies to Word 2010 as well, but not all. For a complete rundown of the new features in Word 2010, see the Changes in Word 2010 article on the TechNet site.
Near the end of that article is a section with information on migrating from Office 97-2003 to Office 2010, including VBA settings. As useful as this information may be for system administrators, for the average Word user who simply wants to avoid having to recreate customizations when upgrading, the process is way too complicated. It may be quicker to simply re-enter your customizations manually.
Skip Word's automatic corrections entirely
On a related note, many people find Word's AutoCorrect and "Replace text as you type" features more trouble than they're worth. To disable these settings in Word 2003, click Tools > AutoCorrect Options and uncheck the options you don't want on the AutoCorrect tab. To access the AutoCorrect options in Word 2007, click the Office button, choose Word Options > Proofing, click the AutoCorrect Options button, and choose the AutoCorrect tab. In Word 2010, click File > Options > Proofing > AutoCorrect Options > AutoCorrect.
Tomorrow: A free add-on makes it easy to clean up Word formatting.