published website: www.sterreizen.be

I encounter an error message when I export the website. The message is 'an error occured during the export of the file' (free translation from Dutch message 'Er is een fout opgetreden tijdens het exproteren van het bestand').

The file: /wwwroot/imemail/imEmailForm_1p2m152x.php

The form is shown like it has to, but after completing the form and sendig it, you get a message on the screen: 

Page Not Found (404)The page you requested is not available.

This is very unfortunate as I need that part of my website very urgent.

Earlier, the export worked perfect, lately these error messages appear frequently, even for other kind of files.

How can I solve this problem?

Kind regards,

Luc