Thanks pilou2 for the quick response.
I rewrote line 21 of the SQL and pasted it in the sql tab, but it did not work.
I reinstalled all of ZEN-CART and pasted "mysql_japanese_install.sql" and no error. Thanks.
The error in line #1136-1 seems to have been caused by a double upload as you suggested.
Now I have no more problems adding products, and the storfront page is displaying well.

I was able to proceed and uploaded 'mysql_japanese_admin_menu.sql' as well.
I uploaded the admin-JP contents to the admin folder using FTP software.
At this time, there was one error that 'myadmin/includes/languages/japanese/images/buttons/button_display.gif' could not be uploaded.

I logged into the admin panel, but it was not in Japanese.
I tried uploading 'mysql_japanese_config.sql' in the SQL folder, and the 'japanese' combo box appeared on the admin screen and I was able to make the admin screen Japanese.

However, when I go to the modules menu to view payment modules, etc,

'Error: Module could not be loaded because the corresponding language file does not exist: /mydomain/myfolder/includes/languages/japanese/modules/modules/payment/authorizenet.php'

'Error: Module could not be loaded because the corresponding language file does not exist: /mydomain/~
I get seme 10 errors, and similar errors for other shipping modules, etc.'

Are there any other files that should be uploaded?