Member:
Markus ⋅
Date: February 20, 2010, 02:39 PM
⋅ Subject: "Re: registration email expiration"
So he got the "Your activation link appears to be invalid or outdated" message? (Or "Your activation link is broken or incomplete"?)
There is actually no time-based expiration defined. However, the link is one-use-only. Did his account still show as "validating" at the time he received this error? In either case, you didn't need to delete it --- you could have just validated it from the admin panel.
On a related note, one thing that will invalidate your activation link is if you try to use "password recovery" before you activate your account.