Hello pinjosi,
thank you for your contribution!
When you do translations, please always use the latest en-GB files as the basis of your translation:
The latest version of the VM2 backend language files is here:
https://dev.virtuemart.net/svn/virtuemart/trunk/virtuemart/administrator/language/The latest version of the VM2 frontend language files is here:
https://dev.virtuemart.net/svn/virtuemart/trunk/virtuemart/language/If you use older language files, they will probably not work with the latest version of VirtueMart 2. The file you took as the basis of your translation is almost 5 months old. In the meantime it has changed quite a lot.

I just had a short look at your file. At the end of each line you always have a CR (Carriage Return) plus an LF (Line Feed). Please use LF only.
COM_VIRTUEMART_FEATURED=Aanbieding
CRLF [wrong]
COM_VIRTUEMART_FEATURED=Aanbieding
LF [correct]
Hope we will see some more translations from you soon.
