diff --git base/univention-quota/umc/python/quota/tools.py base/univention-quota/umc/python/quota/tools.py
index e65351a794..6c72b2a882 100644
--- base/univention-quota/umc/python/quota/tools.py
+++ base/univention-quota/umc/python/quota/tools.py
@@ -42,8 +42,6 @@ import os
 import re
 import subprocess
 
-import tornado.process
-
 import univention.management.console as umc
 from univention.config_registry import handler_set
 from univention.lib import fstab
@@ -83,7 +81,7 @@ class UserQuota(dict):
             self[time] = value
 
 
-def repquota(partition, callback):
+def repquota(partition):
     # find filesystem type
     fs = fstab.File()
     part = fs.find(spec=partition)
@@ -94,8 +92,9 @@ def repquota(partition, callback):
     # -C == do not try to resolve all users at once
     # -v == verbose
     cmd = ['/usr/sbin/repquota', '-C', '-v', partition] + args
-    proc = tornado.process.Subprocess(cmd, stdout=subprocess.PIPE)
-    proc.set_exit_callback(functools.partial(callback, proc.stdout))
+    proc = subprocess.Popen(cmd, stdout=subprocess.PIPE)
+    stdout, stderr = proc.communicate()
+    return (stdout, proc.returncode)
 
 
 def repquota_parse(partition, output):
diff --git base/univention-quota/umc/python/quota/user.py base/univention-quota/umc/python/quota/user.py
index e5451bc04d..9822de34bd 100644
--- base/univention-quota/umc/python/quota/user.py
+++ base/univention-quota/umc/python/quota/user.py
@@ -42,7 +42,7 @@ from univention.lib import fstab
 from univention.management.console import Translation
 from univention.management.console.error import UMC_Error
 from univention.management.console.log import MODULE
-from univention.management.console.modules.decorators import sanitize, simple_response, threaded
+from univention.management.console.modules.decorators import sanitize, simple_response, threaded, SimpleThread
 from univention.management.console.modules.quota import tools
 from univention.management.console.modules.sanitizers import IntegerSanitizer, PatternSanitizer, StringSanitizer
 
@@ -68,8 +68,12 @@ class Commands(object):
         partitionDevice = request.options['partitionDevice']
         self._check_error(partitionDevice)
 
-        callback = functools.partial(self._users_query, partitionDevice, request)
-        tools.repquota(request.options['partitionDevice'], callback)
+        def _thread(request):
+            stdout, returncode = tools.repquota(request.options['partitionDevice'])
+            return self._users_query(partitionDevice, request, stdout, returncode)
+
+        thread = SimpleThread('repquota', _thread, lambda r, t: self.thread_finished_callback(r, t, request))
+        thread.run(request)
 
     def _users_query(self, partition, request, stdout, status):
         """
@@ -82,7 +86,7 @@ class Commands(object):
         devs = fstab.File()
         devs.find(spec=partition)
 
-        callbackResult = stdout.read().splitlines()
+        callbackResult = stdout.splitlines()
 
         # skip header
         header = 0
@@ -93,8 +97,7 @@ class Commands(object):
             pass
         output = [x.decode('UTF-8', 'replace') for x in callbackResult[header + 1:]]
         quotas = tools.repquota_parse(partition, output)
-        result = [q for q in quotas if request.options['filter'].match(q['user'])]
-        self.finished(request.id, result)
+        return [q for q in quotas if request.options['filter'].match(q['user'])]
 
     @sanitize(
         partitionDevice=StringSanitizer(required=True),