crazy error - anyone ever seen this behavior

I have a simple classic ASP site pulling data for displaying itemsfrom an Access database - piece of cake, right?

Well, after making some mods to the code - the page is really acting up. When I click a menu item to navigate to a new list of items, I get a poppup error from IE 7 saying the page cannot be displayed, and the operation has been aborted. When I click on OK, I am shown the standard IE 7 "this page cannot be displayed.....Most likely Causes....yada yada yada" You've all seen that page.

Well, from there, if I click the browser back button, I land on the page I was trying all along (when I received the error), and it is displaying just fine. If I close IE and come back to the site 5 minutes later and click the exact same menu item, the page loads up just fine....and can give the error another 5 minutes later. It's very erradic and unpredictable.

Has anyone ever had a page behave this way, or figure out what caused it. I have been staring at my code for 2 hours now and can't see anything that should cause any error - and the error I am getting doesn't look like an ASP error at all. Any insights would be appreciated.

TIA

BT