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Frequently visited

Frequently asked questions

  • I am looking for a domain name registrant. Where can I look it up?

    The Whois is an easy-to-use tool for checking the availability of a .nl domain name. If the domain name is already taken, you can see who has registered it.

    On the page looking up a domain name you will find more information about what a domain name is, how the Whois works and how the privacy of personal data is protected. Alternatively, you can go straight to look for a domain name via the Whois.

  • I would like to transfer my domain name to another registrar. What is the procedure?

    To get your domain name transferred, you need the token (unique ID number) for your domain name. Your existing registrar has the token and is obliged to give it to you within five days, if you ask for it. The procedure for changing your registrar is described on the page transferring your domain name.

  • The details registered about me/my company are incorrect or out of date. How can I get them updated?

    To update the contact details associated with your domain name, you need to contact your registrar. Read more about updating contact details.

  • Why is my domain name in quarantine?

    When a domain name is cancelled, we aren't told the reason, so we can't tell you. You'll need to ask your registrar. The advantage of quarantine is that, if a name's cancelled by mistake, you can always get it back.

    One common reason is that the contract between you and your registrar says you've got to renew the registration every year. If you haven't set up automatic renewal and you don't renew manually, the registration will expire.

  • Ik heb een klacht over mijn provider/registrar. Kan ik daarvoor bij SIDN terecht?

    Wanneer je een klacht hebt over of een geschil met je registrar dan zijn er verschillende mogelijkheden om tot een oplossing te komen. Hierover lees je meer op pagina klacht over registrar. SIDN heeft geen formele klachtenprocedure voor het behandelen van een klacht over jouw registrar.

  • What conditions do I have to meet as a registrar?

    Would you like to be able to register domain names for customers or for your own organisation by dealing directly with SIDN? If so, you can become a .nl registrar. Read more about the conditions and how to apply for registrar status on the page becoming a registrar.

More frequently asked questions

The Computer Security Incident Response Team (CSIRT)

We investigate all security breaches on our ICT infrastructure.

DNS abuse

What is our mission?

Our mission is to provide SIDN with proactive and reactive support by maintaining and continually seeking to improve the security of our services.

What are our goals?

  • We are the single trusted point for computer security matters.

  • We promote awareness of computer security issues.

  • We make recommendations regarding computer security.

  • We support the resolution of computer security incidents.

  • We actively address threats to our services.

What do we protect?

What are we responsible for?

  • The Domain Registration System

  • The resolving of .nl domain names

  • The .nl name servers and zone file

  • The Is and Whois for .nl domain names

  • Our websites (both public and restricted access)

  • The technical infrastructure that secures our offices

  • All other ICT infrastructure

How can you reach us?

  • Preferably by e-mail: csirt@sidn.nl

  • If you want to encrypt your message? Please use our S/MIME certificaat. Here you find the entire certificate chain.

  • You can call us between 08:30 and 17:00 (Dutch time) on +31 26 352 5512.

  • Our mailing address: SIDN F.a.o. SIDN CSIRT PO Box 5022 6802 EA  Arnhem The Netherlands

Contact person:

Profielfoto van Ferry Stelte, CISO bij SIDN

Ferry Stelte

Chief Information Security Officer