diff --git a/youtube_dl/__init__.py b/youtube_dl/__init__.py
index f9898082a..9bb952457 100644
--- a/youtube_dl/__init__.py
+++ b/youtube_dl/__init__.py
@@ -438,7 +438,7 @@ def parse_retries(retries):
     with YoutubeDL(ydl_opts) as ydl:
         # Update version
         if opts.update_self:
-            update_self(ydl.to_screen, opts.verbose, ydl._opener, opts.prefer_insecure)
+            update_self(ydl.to_screen, opts.verbose, ydl._opener)
 
         # Remove cache dir
         if opts.rm_cachedir:
diff --git a/youtube_dl/options.py b/youtube_dl/options.py
index 4a6067cb8..7d1bbc021 100644
--- a/youtube_dl/options.py
+++ b/youtube_dl/options.py
@@ -534,7 +534,7 @@ def _comma_separated_values_options_callback(option, opt_str, value, parser):
     workarounds.add_option(
         '--prefer-insecure',
         '--prefer-unsecure', action='store_true', dest='prefer_insecure',
-        help='Use an unencrypted connection to retrieve information whenever possible')
+        help='Use an unencrypted connection to retrieve information about the video. (Currently supported only for YouTube)')
     workarounds.add_option(
         '--user-agent',
         metavar='UA', dest='user_agent',
diff --git a/youtube_dl/update.py b/youtube_dl/update.py
index d9d95d2a1..ebce9666a 100644
--- a/youtube_dl/update.py
+++ b/youtube_dl/update.py
@@ -28,10 +28,10 @@ def rsa_verify(message, signature, key):
     return expected == signature
 
 
-def update_self(to_screen, verbose, opener, prefer_insecure=False):
+def update_self(to_screen, verbose, opener):
     """Update the program file with the latest version from the repository"""
 
-    UPDATE_URL = '//rg3.github.io/youtube-dl/update/'
+    UPDATE_URL = 'https://rg3.github.io/youtube-dl/update/'
     VERSION_URL = UPDATE_URL + 'LATEST_VERSION'
     JSON_URL = UPDATE_URL + 'versions.json'
     UPDATES_RSA_KEY = (0x9d60ee4d8f805312fdb15a62f87b95bd66177b91df176765d13514a0f1754bcd2057295c5b6f1d35daa6742c3ffc9a82d3e118861c207995a8031e151d863c9927e304576bc80692bc8e094896fcf11b66f3e29e04e3a71e9a11558558acea1840aec37fc396fb6b65dc81a1c4144e03bd1c011de62e3f1357b327d08426fe93, 65537)
@@ -40,13 +40,9 @@ def update_self(to_screen, verbose, opener, prefer_insecure=False):
         to_screen('It looks like you installed youtube-dl with a package manager, pip, setup.py or a tarball. Please use that to update.')
         return
 
-    def guess_scheme(url, insecure=False):
-        return 'http%s:%s' % ('' if insecure is True else 's', url)
-
     # Check if there is a new version
     try:
-        newversion = opener.open(guess_scheme(
-            VERSION_URL, prefer_insecure)).read().decode('utf-8').strip()
+        newversion = opener.open(VERSION_URL).read().decode('utf-8').strip()
     except Exception:
         if verbose:
             to_screen(encode_compat_str(traceback.format_exc()))
@@ -58,8 +54,7 @@ def guess_scheme(url, insecure=False):
 
     # Download and check versions info
     try:
-        versions_info = opener.open(guess_scheme(
-            JSON_URL, prefer_insecure)).read().decode('utf-8')
+        versions_info = opener.open(JSON_URL).read().decode('utf-8')
         versions_info = json.loads(versions_info)
     except Exception:
         if verbose: