On some items, I have broken internal links: "404 - Item not found"

Here are a couple of examples:
[Omitted to get past "spam detected" warning]

I'm running:
Joomla 3.2.7
K2 2.6.7

Search Engine Friendly URLs is disabled.
The redirect plug-in is disabled.

I appreciate any assistance you can offer. Thank you.

– Michael

Can you send us some links ?
You can omit the http:// part

polyoutdoorfurniture [dot] com/for-the-birds/bird-feeders/upside-down-suet-feeder

polyoutdoorfurniture [dot] com/for-the-birds/bird-feeders/swing-bird-feeder

If you are using sh404sef or a similar extension this could be related to the extension's cache.

Are you using also K2's advanced SEF?