Hello Pierre,
please send us your link to your site by email, so we can check it (
info@rupostel.com) The default configuration works for 95 percent of our customers, but you most probably have some encoding issues with your language files. Do you get any errors in the configurator? Are you running your site on windows server?
The configuration file must be writable here:
/administrator/components/com_virtuemart/classes/onepage/onepage.cfg.php
(this file can be manually edited)
Payment html are saved here (if you use it):
/administrator/components/com_virtuemart/classes/payment/onepage/
It is also strongly recommended that your "header" encoding equals html encoding (in meta tags). Some servers automatically issue incorrect encoding. Some of the older language files for VirtueMart were saved in other than utf8 encoding - for this there is a checkbox at the display tab. Some servers don't work with BOM at the beginning of the language files and this causes many problems. This all is very specific to your server configuration, but we can fix this within minutes.
Our component does not alter paypal redirection anyhow, but when php debugging is on, some header data can be sent before redirect by any part of joomla.
We also recommend to check Firefox error console (ctrl + shift + J ) for any errors. Our component does not load when a javascript error is detected.