Some pages defaulting to theme index.php

Hi all,

I developed a custom theme on my local machine and added a couple of test pages. Everything appears to work fine locally.

I've since migrated to a host following the steps provided in Zac's video. On the surface, everything looks like it's working properly... the custom theme home page loads and I can navigate to blog entries and custom post types.

The problem is that some of the pages (added in the regular "Pages" admin section) do not load. Instead, when you click on the menu link, it defaults to the theme's index page. The other complication is that some pages work (i.e. they load fine), and others just default to the index. To that end, I can't seem to find out why some are working and others aren't. I've even tried adding a new page from scratch with simple text content, but to no avail.

I've tried updating permalinks. The "Post Name" format further cripples functionality, where the "Default" and a custom structure " /index.php/%postname%/" allows me to navigate to at least one page successfully.

I've also disabled all of the host's default plugins, so the only ones activated are the ones that were on my local machine. The host is Yahoo Small Business, which I'm reading is a terrible choice for a WP host, but that's what my friend currently has.

Any advice on how to trouble shoot this issue would be greatly appreciated!