Since you don't say what version of Word you have, I'll have to assume
that you have Word 2003 (the current version). Italian proofing tools
(dictionary, thesaurus, etc.) are included with the Croatian, German,
Italian, and Slovenian language versions of Word 2003. If you have one
of these language versions of Word 2003, you can add the Italian
proofing tools feature to your existing installation by clicking on
Start | Control Panel | Add/Remove Programs | Microsoft Word 2003 |
Change | Add/Remove Features. If you do not have one of these language
versions of Word 2003, you can purchase the Proofing Tools CD for Office
2003, and install the Italian proofing tools from the Proofing Tools CD.

Marianne wrote:

When I set my text to Italian for the first time, it didn't ask me if I
wanted to install the spellcheck. It went straight to telling me it cannot
find the proper documents to check it. I tried to do a repair and
troubleshoot, but nothing worked. I have all the discs I need, but I do not
know how to install it manually.