Welcome to Rob Groen's website

The Internet Jigsaw

Internet and internet systems are like one big jigsaw. Every piece has to be on the right place. If just one piece isn't right than you won't get the result you hoped for.

E-commerce specialist

I am a E-commerce specialist and can help you with many questions about this fantastic way of selling you products or services. In the late '90 I started a web shop for selling white-goods over the Internet on the Dutch marked. I was the first one who did that and there was no software like Drupal of OS-Commerce. I had to invent it all by myself. It was a great time!.
The shop was very successful and some day a big company made me an offer that I couldn't refuse. So I sold my e-commerce business.

Now I use my knowledge to advice and help other e-commerce companies to get better, grow and make more profit. My strength is the combination between technique and commerce.

Linux specialist

I am a Linux specialist and work with Linux since 1997. I am using mainly Debian based distributions like Debian and Ubuntu.
Please let me help you to find the pieces you need and how to stuck them together.Visit my Linux Tips & Trick page to see some helpful solutions.

Scheveningen Luxemburg Scheveningen

Classic SLS Rally

Since 1995 I drive with the technical service and repair group in the Classic SLS Rally. this Rally is for old car dated before 1975 and they drive from Scheveningen, a famous city on the west coast from The Netherlands, to downtown Luxembourg city and back again.

The rally includes 2 nightly stays in Belgium.

SLS Rally Medaille

Portfolio overview

A overview with some of my website projects. I prefer building websites in Drupal, Joomla and OS-Commerce.



A website for a new concept where the dry cleaner pick-up the laundry by the costumer at home. After cleaning it will be delivered client.

The website is build in Joomla and extended with some special modules to accomplish the wishes of the constituent.



Screenshot Witgoedboer

I am the founder of the website "Witgoedboer.nl", Literally translated does it mean "White goods Farmer". That's a kind of Dutch slang for persons who sell washing machines, dishwashers en fridges.

Latest Tips & Tricks

My latests solutions for Linux software problems.
(English Only)

How-To create company logo on ZPanel and Roundcude log-in page


You're hosting a with server ZPanel for multiple customer and you want a for every customer a company logo on the ZPanel and Roundcube log-in page.

Here is How-To do that

Step 1

Create a company logo

Update Drupal with drush without updating all modules

If you want to update Drupal core with drush but you don't want to update all contrib modules you can use this command.

drush up drupal

Strange why this is not in the drush manual

How-to remove the mdash after the text field in Drupal Twitter module

I was struggling around with removing the mdash character from the post on my website. It took some time till I realized that the dmash was NOT in the field-content but that is a field-separator.

Testpage for referen on sohf.nl

This is a testpage with a link to a subscribe page on www.sohf.nl if I click this link I should go to www.sohf.nl on the subscribe page. The sohf website stores the initial HTTP_REFERER in a session that I can recall by filling in the form.

Some more test links

Thunderbird Lightning calendar API (September 2013)

On the 17e of September Google changed the connection and authentication method of ther api for the Google Calendar data.


Fotografie is al sinds mijn jeugd een hobby. In de jaren '70 fotografeerde ik met een 2-hands grootbeeld spiegelreflex camera. Echt een oudje en ondanks zijn leeftijd een prima camera. Dat was in die tijd normaal dat je naast je camera ook een aparte, losse belichtingsmeter bij je had. Immers met de camera kon je niets ander dan scherpstellen, de sluitertijd en het diafragma instellen.