Yes, I was unable to duplicate the error. It worked for me, the email was sent and received perfectly.
The first report came to me secondhand, I was not given a username or anything. On the second report I had the username and it is phpBB3 so I was able to assume the user's permissions and navigate the board as the user, and it worked that way too.
Maybe I should ask what browser they are using, and whether they could confirm they were still logged in. If you know of any other questions to ask, I will ask them if it happens again.