diff --git a/resources/templates/provision/yealink/t42s/y000000000067.cfg b/resources/templates/provision/yealink/t42s/y000000000067.cfg
index 924fb437c5..78c23577a3 100644
--- a/resources/templates/provision/yealink/t42s/y000000000067.cfg
+++ b/resources/templates/provision/yealink/t42s/y000000000067.cfg
@@ -340,7 +340,7 @@ static.security.default_ssl_method =
 static.security.cn_validation = 
 static.security.dev_cert = 
 static.security.ca_cert = 
-static.security.trust_certificates = 
+static.security.trust_certificates = {if $yealink_trust_certificates == "false"}0{elseif $yealink_trust_certificates == "true"}1{/if}
 static.security.user_password = {$var_name}:{$var_password}
 static.security.user_password = {$admin_name}:{$admin_password}
 static.security.user_password = {$user_name}:{$user_password}