diff --git a/src/calibre/gui2/update.py b/src/calibre/gui2/update.py
index 9ce55d0..f9521d7 100644
--- a/src/calibre/gui2/update.py
+++ b/src/calibre/gui2/update.py
@@ -1,19 +1,17 @@
 __license__   = 'GPL v3'
 __copyright__ = '2008, Kovid Goyal <kovid at kovidgoyal.net>'
 
-import re, binascii, cPickle, ssl, json
+import binascii, cPickle
 from future_builtins import map
 from threading import Thread, Event
 
 from PyQt5.Qt import (QObject, pyqtSignal, Qt, QUrl, QDialog, QGridLayout,
-        QLabel, QCheckBox, QDialogButtonBox, QIcon)
+        QLabel, QDialogButtonBox, QIcon)
 
-from calibre.constants import (__appname__, __version__, iswindows, isosx,
+from calibre.constants import (__appname__, iswindows, isosx,
         isportable, is64bit, numeric_version)
 from calibre import prints, as_unicode
-from calibre.utils.config import prefs
-from calibre.utils.https import get_https_resource_securely
-from calibre.gui2 import config, dynamic, open_url
+from calibre.gui2 import dynamic, open_url
 from calibre.gui2.dialogs.plugin_updater import get_plugin_updates_available
 
 URL = 'https://code.calibre-ebook.com/latest'
@@ -30,35 +28,7 @@ def get_download_url():
 
 
 def get_newest_version():
-    try:
-        icon_theme_name = json.loads(I('icon-theme.json', data=True))['name']
-    except Exception:
-        icon_theme_name = ''
-    headers={
-        'CALIBRE-VERSION':__version__,
-        'CALIBRE-OS': ('win' if iswindows else 'osx' if isosx else 'oth'),
-        'CALIBRE-INSTALL-UUID': prefs['installation_uuid'],
-        'CALIBRE-ICON-THEME': icon_theme_name,
-    }
-    try:
-        version = get_https_resource_securely(URL, headers=headers)
-    except ssl.SSLError as err:
-        if getattr(err, 'reason', None) != 'CERTIFICATE_VERIFY_FAILED':
-            raise
-        # certificate verification failed, since the version check contains no
-        # critical information, ignore and proceed
-        # We have to do this as if the calibre CA certificate ever
-        # needs to be revoked, then we wont be able to do version checks
-        version = get_https_resource_securely(URL, headers=headers, cacerts=None)
-    try:
-        version = version.decode('utf-8').strip()
-    except UnicodeDecodeError:
-        version = u''
-    ans = NO_CALIBRE_UPDATE
-    m = re.match(ur'(\d+)\.(\d+).(\d+)$', version)
-    if m is not None:
-        ans = tuple(map(int, (m.group(1), m.group(2), m.group(3))))
-    return ans
+    return NO_CALIBRE_UPDATE
 
 
 class Signal(QObject):
@@ -81,12 +51,6 @@ class CheckForUpdates(Thread):
             calibre_update_version = NO_CALIBRE_UPDATE
             plugins_update_found = 0
             try:
-                version = get_newest_version()
-                if version[:2] > numeric_version[:2]:
-                    calibre_update_version = version
-            except Exception as e:
-                prints('Failed to check for calibre update:', as_unicode(e))
-            try:
                 update_plugins = get_plugin_updates_available(raise_error=True)
                 if update_plugins is not None:
                     plugins_update_found = len(update_plugins)