Domain checker shows all .nl domains taken

So I've added a custom whois file to the root of my whmcs installation to use the API of my registrar. I've edited that file correctly to use my account at the registrar. In the includes/whoisserver.php i've changed the line "#.nl|whois.domain-registry.nl|is free" with ".nl|http://www.raswebsolutions.nl/mdr_whois.php?domain=|HTTPREQUEST-nl is free" But when I check a .nl domain. It shows all as taken while some definately are not. Since http requests automatically get redirected to htt

any chance you're hitting the SIDN WHOIS lookup limits? I know the default whoisserver file uses the port43 address, so likely has a whois limit of 15 per day; the website has a 500 lookup limit - so i'm not sure if/what the limit would be via API? the following may not help you directly, but a fellow Dutch WHMCS user told me that he uses... .nl|http://whois.domain-registry.nl/is?domain=|HTTPREQUEST-is free as it gives more consistent results that the default WHOIS (returns availa