[Solved] Certain products in certain categories unavailable

[shaiss]

Still setting up the shop, but if you goto the homepage you'll see its mostly there:
http://hitek51.com/

goto the computers category and choose any product and it works.
But goto any other category, the products are listed, click on anyone. Instead of seeing the products page you get the "page not available" "We're sorry, but the Web address you entered is no longer available" message.

My thinking is that this has something to do with the links. But why would one category work and others not?

Any ideas?

Please let me know if it would help to post any B/O screenshots.

I noticed this in the apache error log:
[Mon Mar 08 18:54:00 2010] [error] [client 66.104.92.200] File does not exist: /home/shaiss/public_html/HITEK51.COM/Electro_Mechanical, referer: http://hitek51.com/26-Fans

Update--Fixed it by changing the friendly URL to all lowercase