The NSURLErrorDomain error when installing

I’ve searched this forum several times, read the pertinent Codex articles, and searched the Web for hours. I am unable to install WordPress because I keep getting the NSURLErrorDomain message in Safari when trying to access install.php. Of course, this is just the Safari message. But the page will not load in any browser. No permission settings fixes this. The site is hosted on an Apache server at pair Networks (which certainly can be trusted to get php right) using php 4.3.10.

Searches here show others running into this problem but well after install. For some, it cropped up during an upgrade. For others, it just surfaced when installing a new plug-in.

I’m not php savvy but I have been reasonably successful in the past installing all kinds of php applications — CMS, other blog systems, forums, etc.

But now I’m stuck and stymied.

Thanks.

Ken