Why do I get "We're sorry, an internal error has occurred"

This page is displayed whenever an error has occurred, so the shop visitor won't see the original error message rendered by ASP.NET. Unfortunately, it tells us nothing about the real error that has occurred. So, if you have to investigate the causes behind this error, it's important to turn this custom error page off and display the original error instead.

To do so, we have to edit the web.config. Search for the following node:

<customErrors defaultRedirect="errorpage.htm" mode="RemoteOnly">
    <error statusCode="404" redirect="~/404" />

and alter it as follows:

<customErrors mode="Off" />