Welcome to the new NSA website!
The old version of the website can be found at old.nsaweb.nl. You can log in there with no additional steps.
To login to the new site, you must first set a password. Please go to /en/leden/wachtwoord-reset/, and fill in your email. (The same email you have always used on nsaweb.nl)
Barring any problems with sending emails, you will get a link to set a new password :)