Hi Lenny, please refer this following link, it tell you how to add Cantonese input in Windows 7:
http://computer.discuss.com.hk/viewthread.php?tid=10875018&extra=page%3D1
Please Note: Since the website is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.
Hope it helps.
Regards,
Leo
Huang
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