diff --git a/lib/Froxlor/Api/Commands/Admins.php b/lib/Froxlor/Api/Commands/Admins.php
index 044933db..2b40a799 100644
--- a/lib/Froxlor/Api/Commands/Admins.php
+++ b/lib/Froxlor/Api/Commands/Admins.php
@@ -286,7 +286,9 @@ class Admins extends ApiCommand implements ResourceEntity
 				Response::standardError('loginnameexists', $loginname, true);
 			} elseif (preg_match('/^' . preg_quote(Settings::Get('customer.accountprefix'), '/') . '([0-9]+)/', $loginname)) {
 				// Accounts which match systemaccounts are not allowed, filtering them
-				Response::standardError('loginnameissystemaccount', Settings::Get('customer.accountprefix'), true);
+				Response::standardError('loginnameisusingprefix', Settings::Get('customer.accountprefix'), true);
+			} elseif (function_exists('posix_getpwnam') && !in_array("posix_getpwnam", explode(",", ini_get('disable_functions'))) && posix_getpwnam($loginname)) {
+				Response::standardError('loginnameissystemaccount', $loginname, true);
 			} elseif (!Validate::validateUsername($loginname)) {
 				Response::standardError('loginnameiswrong', $loginname, true);
 			} elseif (!Validate::validateEmail($email)) {
diff --git a/lib/Froxlor/Api/Commands/Customers.php b/lib/Froxlor/Api/Commands/Customers.php
index da0f1a31..0eeb8ffd 100644
--- a/lib/Froxlor/Api/Commands/Customers.php
+++ b/lib/Froxlor/Api/Commands/Customers.php
@@ -429,7 +429,7 @@ class Customers extends ApiCommand implements ResourceEntity
 
 						// Additional filtering for Bug #962
 						if (function_exists('posix_getpwnam') && !in_array("posix_getpwnam", explode(",", ini_get('disable_functions'))) && posix_getpwnam($loginname)) {
-							Response::standardError('loginnameissystemaccount', Settings::Get('customer.accountprefix'), true);
+							Response::standardError('loginnameissystemaccount', $loginname, true);
 						}
 					} else {
 						$accountnumber = intval(Settings::Get('system.lastaccountnumber')) + 1;
diff --git a/tests/Admins/AdminsTest.php b/tests/Admins/AdminsTest.php
index 6c2a8492..ff83199b 100644
--- a/tests/Admins/AdminsTest.php
+++ b/tests/Admins/AdminsTest.php
@@ -86,7 +86,7 @@ class AdminsTest extends TestCase
 			'name' => 'Testreseller'
 		];
 
-		$this->expectExceptionMessage('You cannot create accounts which are similar to system accounts (as for example begin with "web"). Please enter another account name.');
+		$this->expectExceptionMessage('You cannot create accounts that begin with "web", as this prefix is set to be used for the automatic account-naming. Please enter another account name.');
 		Admins::getLocal($admin_userdata, $data)->add();
 	}
 
diff --git a/tests/Customers/CustomersTest.php b/tests/Customers/CustomersTest.php
index 401049c5..214a453d 100644
--- a/tests/Customers/CustomersTest.php
+++ b/tests/Customers/CustomersTest.php
@@ -491,7 +491,7 @@ class CustomersTest extends TestCase
 			)
 		];
 
-		$this->expectExceptionMessage('You cannot create accounts which are similar to system accounts (as for example begin with "web"). Please enter another account name.');
+		$this->expectExceptionMessage('You cannot create accounts that begin with "web", as this prefix is set to be used for the automatic account-naming. Please enter another account name.');
 		Customers::getLocal($admin_userdata, $data)->add();
 	}