I've compared the site definitions on both computers and they are identical. I deleted the definition on my desktop and copied the definition from my laptop but it didn't help. I deleted all the site files on my desktop and copied all the same files from my notebook. I checked content regions on other pages on the site and they are working properly. It appears to only affect the one page.
If I try to define a new content region, I'm asked to define a connection. The connection set up for this site isn't appearing. See the attachment. When I click on Define, the next window has the New button grayed out.
Can you give me other recommendations to look at?