How do I stop Excel from checking the validity of hyperlinks before it opens them?

A registry setting can change this behavior and force Excel to simply launch URL's in the default browser. There could be security implications, so be sure to read the following article carefully and decide if it's the right thing for you to do.

http://support.microsoft.com/kb/218153#FixItForMeAlways

I ran the "Fix it for me" application after several unsuccessful attempts to manually make the registry edits.

Now my hyperlinks launch in the default browser, without the pre-check, regardless if it's clicked by the user, or programmatically launched in VBA.