I launched an xpages form back in November which is a typical 2-stage registration process. 

On stage one submit, I have SSJS running to generate an html email containing an activation button which runs some further ssjs, adds the user to the webusers.nsf Directory (directoy assistance) and presents another xpage where they can hit another button to take them to the profile page (another xpage) to complete the creative profile form for submission.

The problem is we now have 60-odd users who have completed the stage two profile, but nearly 100 users who got to stage 1 but were unable to complete the profile. The main issue is that regardless of platform or device (Win 10, ios on iPhones/iPads, Android devices) many of these users are unable to reach the profile form due to an error "The site can't be reached. The connection was reset. ERR_CONNECTION_RESET". I have tried and failed to reproduce this problem on my Win 10/latest Chrome laptop or on an iPhone 6s, and no-one within the company has reproduced it either, but it seems to be affecting all devices/OSs.

We have contacted our Domino server hosting provider but they don't seem to have any ideas either.