diff --git a/apps/user_ldap/group_proxy.php b/apps/user_ldap/group_proxy.php
index 68d2efe38718dd00d1ed9bc8a4610c833f765e50..75e7cd46336328e8320447f6bb9f037ce8ca3aac 100644
--- a/apps/user_ldap/group_proxy.php
+++ b/apps/user_ldap/group_proxy.php
@@ -76,8 +76,15 @@ class Group_Proxy extends lib\Proxy implements \OCP\GroupInterface {
 			if(isset($this->backends[$prefix])) {
 				$result = call_user_func_array(array($this->backends[$prefix], $method), $parameters);
 				if(!$result) {
-					//not found here, reset cache to null
-					$this->writeToCache($cacheKey, null);
+					//not found here, reset cache to null if group vanished
+					//because sometimes methods return false with a reason
+					$groupExists = call_user_func_array(
+						array($this->backends[$prefix], 'groupExists'),
+						array($gid)
+					);
+					if(!$groupExists) {
+						$this->writeToCache($cacheKey, null);
+					}
 				}
 				return $result;
 			}
diff --git a/apps/user_ldap/user_proxy.php b/apps/user_ldap/user_proxy.php
index 6a75bae3815f0cbdb1b4b416cc9dacc58192d44d..7e5b9045df3f42064ef0e75a71ece3adc2a7c277 100644
--- a/apps/user_ldap/user_proxy.php
+++ b/apps/user_ldap/user_proxy.php
@@ -76,8 +76,15 @@ class User_Proxy extends lib\Proxy implements \OCP\UserInterface {
 			if(isset($this->backends[$prefix])) {
 				$result = call_user_func_array(array($this->backends[$prefix], $method), $parameters);
 				if(!$result) {
-					//not found here, reset cache to null
-					$this->writeToCache($cacheKey, null);
+					//not found here, reset cache to null if user vanished
+					//because sometimes methods return false with a reason
+					$userExists = call_user_func_array(
+						array($this->backends[$prefix], 'userExists'),
+						array($uid)
+					);
+					if(!$userExists) {
+						$this->writeToCache($cacheKey, null);
+					}
 				}
 				return $result;
 			}