diff --git a/src/main/java/org/gcube/portal/ldapexport/LDAPSync.java b/src/main/java/org/gcube/portal/ldapexport/LDAPSync.java
index 85f08a7..adeef01 100644
--- a/src/main/java/org/gcube/portal/ldapexport/LDAPSync.java
+++ b/src/main/java/org/gcube/portal/ldapexport/LDAPSync.java
@@ -212,8 +212,8 @@ public class LDAPSync implements Runnable {
 			
 			_log.debug("Trying read  sshPublicKey for " + user.getScreenName());
 			String sshPublicKey = new LiferayUserManager().readCustomAttr(user.getUserId(), SSH_PUBLIC_KEY_ATTR).toString();
-			
-			updateUserInLDAP(user.getScreenName(), user.getFirstName(), lastName, user.getFullName(), user.getEmailAddress(), "{SHA}"+user.getPassword(), sshPublicKey, ctx, filter);
+			if (user.getFirstName() != null && user.getFirstName().compareTo("") != 0)
+				updateUserInLDAP(user.getScreenName(), user.getFirstName(), lastName, user.getFullName(), user.getEmailAddress(), "{SHA}"+user.getPassword(), sshPublicKey, ctx, filter);
 			_log.debug("Updated " + user.getScreenName());
 		}			
 		_log.debug("LDAP Users Sync cycle done");