diff --git a/packages/xo-server-auth-ldap/src/index.js b/packages/xo-server-auth-ldap/src/index.js
index 5e2152b1c..8120a18c8 100644
--- a/packages/xo-server-auth-ldap/src/index.js
+++ b/packages/xo-server-auth-ldap/src/index.js
@@ -45,7 +45,7 @@ class AuthLdap {
 
       const {tlsOptions} = clientOpts
 
-      tlsOptions.rejectUnauthorized = !checkCertificate
+      tlsOptions.rejectUnauthorized = checkCertificate
       if (certificateAuthorities) {
         tlsOptions.ca = certificateAuthorities.map(path => readFileSync(path))
       }