New Post: Error message instead of showing related products

Hi Geoff!

Thanks for looking for me!
It works! When I turn on friendly urls, the related products work. But: there is a problem. When I turn on friendly urls, I cannot reach the store backoffice anymore. Instead of the backoffice, it shows the homepage of my site. When I turn off friendly urls again, I can go to my backoffice, and have the same problem back with my related products...

Regards, Jeanet