Download MSVC compiler/linker & Windows SDK without installing full Visual Studio

!README.md

This downloads standalone MSVC compiler, linker & other tools, also headers/libraries from Windows SDK into portable folder, without installing Visual Studio. Has bare minimum components - no UWP/Store/WindowsRT stuff, just files & tools for native desktop app development.

Run py.exe portable-msvc.py and it will download output into msvc folder. By default it will download latest available MSVC & Windows SDK - currently v14.40.33807 and v10.0.26100.0.

You can list available versions with py.exe portable-msvc.py --show-versions and then pass versions you want with --msvc-version and --sdk-version arguments.

To use cl.exe/link.exe first run setup_TARGET.bat - after that PATH/INCLUDE/LIB env variables will be updated to use all the tools as usual. You can also use clang-cl.exe with these includes & libraries.

To use clang-cl.exe without running setup.bat, pass extra /winsysroot msvc argument (msvc is folder name where output is stored).

portable-msvc.py

#!/usr/bin/env python3

import io
import os
import sys
import stat
import json
import shutil
import hashlib
import zipfile
import tempfile
import argparse
import subprocess
import urllib.error
import urllib.request
from pathlib import Path

OUTPUT = Path("msvc")         # output folder
DOWNLOADS = Path("downloads") # temporary download files

# NOTE: not all host & target architecture combinations are supported

DEFAULT_HOST = "x64"
ALL_HOSTS    = "x64 x86 arm64".split()

DEFAULT_TARGET = "x64"
ALL_TARGETS    = "x64 x86 arm arm64".split()

MANIFEST_URL = "https://aka.ms/vs/17/release/channel"
MANIFEST_PREVIEW_URL = "https://aka.ms/vs/17/pre/channel"

ssl_context = None

def download(url):
  with urllib.request.urlopen(url, context=ssl_context) as res:
    return res.read()

total_download = 0

def download_progress(url, check, name, filename):
  fpath = DOWNLOADS / filename
  if fpath.exists():
    data = fpath.read_bytes()
    if hashlib.sha256(data).hexdigest() == check.lower():
      print(f"\r{name} ... OK")
      return data

  global total_download
  with fpath.open("wb") as f:
    data = io.BytesIO()
    with urllib.request.urlopen(url, context=ssl_context) as res:
      total = int(res.headers["Content-Length"])
      size = 0
      while True:
        block = res.read(1<<20)
        if not block:
          break
        f.write(block)
        data.write(block)
        size += len(block)
        perc = size * 100 // total
        print(f"\r{name} ... {perc}%", end="")
    print()
    data = data.getvalue()
    digest = hashlib.sha256(data).hexdigest()
    if check.lower() != digest:
      exit(f"Hash mismatch for f{pkg}")
    total_download += len(data)
    return data

# super crappy msi format parser just to find required .cab files
def get_msi_cabs(msi):
  index = 0
  while True:
    index = msi.find(b".cab", index+4)
    if index < 0:
      return
    yield msi[index-32:index+4].decode("ascii")

def first(items, cond):
  return next((item for item in items if cond(item)), None)
  

### parse command-line arguments

ap = argparse.ArgumentParser()
ap.add_argument("--show-versions", action="store_true", help="Show available MSVC and Windows SDK versions")
ap.add_argument("--accept-license", action="store_true", help="Automatically accept license")
ap.add_argument("--msvc-version", help="Get specific MSVC version")
ap.add_argument("--sdk-version", help="Get specific Windows SDK version")
ap.add_argument("--preview", action="store_true", help="Use preview channel for Preview versions")
ap.add_argument("--target", default=DEFAULT_TARGET, help=f"Target architectures, comma separated ({','.join(ALL_TARGETS)})")
ap.add_argument("--host", default=DEFAULT_HOST, help=f"Host architecture", choices=ALL_HOSTS)
args = ap.parse_args()

host = args.host
targets = args.target.split(',')
for target in targets:
  if target not in ALL_TARGETS:
    exit(f"Unknown {target} target architecture!")


### get main manifest

URL = MANIFEST_PREVIEW_URL if args.preview else MANIFEST_URL

try:
  manifest = json.loads(download(URL))
except urllib.error.URLError as err:
  import ssl
  if isinstance(err.args[0], ssl.SSLCertVerificationError):
    # for more info about Python & issues with Windows certificates see https://stackoverflow.com/a/52074591
    print("ERROR: ssl certificate verification error")
    try:
      import certifi
    except ModuleNotFoundError:
      print("ERROR: please install 'certifi' package to use Mozilla certificates")
      print("ERROR: or update your Windows certs, see instructions here: https://woshub.com/updating-trusted-root-certificates-in-windows-10/#h2_3")
      exit()
    print("NOTE: retrying with certifi certificates")
    ssl_context = ssl.create_default_context(cafile=certifi.where())
    manifest = json.loads(download(URL))
  else:
    raise

### download VS manifest

ITEM_NAME = "Microsoft.VisualStudio.Manifests.VisualStudioPreview" if args.preview else "Microsoft.VisualStudio.Manifests.VisualStudio"

vs = first(manifest["channelItems"], lambda x: x["id"] == ITEM_NAME)
payload = vs["payloads"][0]["url"]

vsmanifest = json.loads(download(payload))


### find MSVC & WinSDK versions

packages = {}
for p in vsmanifest["packages"]:
  packages.setdefault(p["id"].lower(), []).append(p)

msvc = {}
sdk = {}

for pid,p in packages.items():
  if pid.startswith("Microsoft.VisualStudio.Component.VC.".lower()) and pid.endswith(".x86.x64".lower()):
    pver = ".".join(pid.split(".")[4:6])
    if pver[0].isnumeric():
      msvc[pver] = pid
  elif pid.startswith("Microsoft.VisualStudio.Component.Windows10SDK.".lower()) or \
       pid.startswith("Microsoft.VisualStudio.Component.Windows11SDK.".lower()):
    pver = pid.split(".")[-1]
    if pver.isnumeric():
      sdk[pver] = pid

if args.show_versions:
  print("MSVC versions:", " ".join(sorted(msvc.keys())))
  print("Windows SDK versions:", " ".join(sorted(sdk.keys())))
  exit(0)

msvc_ver = args.msvc_version or max(sorted(msvc.keys()))
sdk_ver = args.sdk_version or max(sorted(sdk.keys()))

if msvc_ver in msvc:
  msvc_pid = msvc[msvc_ver]
  msvc_ver = ".".join(msvc_pid.split(".")[4:-2])
else:
  exit(f"Unknown MSVC version: f{args.msvc_version}")

if sdk_ver in sdk:
  sdk_pid = sdk[sdk_ver]
else:
  exit(f"Unknown Windows SDK version: f{args.sdk_version}")

print(f"Downloading MSVC v{msvc_ver} and Windows SDK v{sdk_ver}")


### agree to license

tools = first(manifest["channelItems"], lambda x: x["id"] == "Microsoft.VisualStudio.Product.BuildTools")
resource = first(tools["localizedResources"], lambda x: x["language"] == "en-us")
license = resource["license"]

if not args.accept_license:
  accept = input(f"Do you accept Visual Studio license at {license} [Y/N] ? ")
  if not accept or accept[0].lower() != "y":
    exit(0)

OUTPUT.mkdir(exist_ok=True)
DOWNLOADS.mkdir(exist_ok=True)


### download MSVC

msvc_packages = [
  f"microsoft.visualcpp.dia.sdk",
  f"microsoft.vc.{msvc_ver}.crt.headers.base",
  f"microsoft.vc.{msvc_ver}.crt.source.base",
  f"microsoft.vc.{msvc_ver}.asan.headers.base",
  f"microsoft.vc.{msvc_ver}.premium.tools.{host}.base.base",
  f"microsoft.vc.{msvc_ver}.pgo.headers.base",
]

for target in targets:
  msvc_packages += [
    f"microsoft.vc.{msvc_ver}.tools.host{host}.target{target}.base",
    f"microsoft.vc.{msvc_ver}.tools.host{host}.target{target}.res.base",
    f"microsoft.vc.{msvc_ver}.crt.{target}.desktop.base",
    f"microsoft.vc.{msvc_ver}.crt.{target}.store.base",
    f"microsoft.vc.{msvc_ver}.crt.redist.{target}.base",
    f"microsoft.vc.{msvc_ver}.premium.tools.host{host}.target{target}.base",
    f"microsoft.vc.{msvc_ver}.pgo.{target}.base",
  ]
  if target in ["x86", "x64"]:
    msvc_packages += [
      f"microsoft.vc.{msvc_ver}.asan.{target}.base",
    ]

for pkg in msvc_packages:
  if pkg not in packages:
    continue
  p = first(packages[pkg], lambda p: p.get("language") in (None, "en-US"))
  for payload in p["payloads"]:
    filename = payload["fileName"]
    download_progress(payload["url"], payload["sha256"], pkg, filename)
    with zipfile.ZipFile(DOWNLOADS / filename) as z:
      for name in z.namelist():
        if name.startswith("Contents/"):
          out = OUTPUT / Path(name).relative_to("Contents")
          out.parent.mkdir(parents=True, exist_ok=True)
          out.write_bytes(z.read(name))


### download Windows SDK

sdk_packages = [
  f"Windows SDK for Windows Store Apps Tools-x86_en-us.msi",
  f"Windows SDK for Windows Store Apps Headers-x86_en-us.msi",
  f"Windows SDK for Windows Store Apps Headers OnecoreUap-x86_en-us.msi",
  f"Windows SDK for Windows Store Apps Libs-x86_en-us.msi",
  f"Windows SDK OnecoreUap Headers x86-x86_en-us.msi",
  f"Windows SDK Desktop Headers x86-x86_en-us.msi",
  f"Universal CRT Headers Libraries and Sources-x86_en-us.msi",
]

for target in targets:
  sdk_packages += [
    f"Windows SDK Desktop Libs {target}-x86_en-us.msi",
  ]

with tempfile.TemporaryDirectory(dir=DOWNLOADS) as d:
  dst = Path(d)

  sdk_pkg = packages[sdk_pid][0]
  sdk_pkg = packages[first(sdk_pkg["dependencies"], lambda x: True).lower()][0]

  msi = []
  cabs = []

  # download msi files
  for pkg in sdk_packages:
    payload = first(sdk_pkg["payloads"], lambda p: p["fileName"] == f"Installers\\{pkg}")
    if payload is None:
      continue
    msi.append(DOWNLOADS / pkg)
    data = download_progress(payload["url"], payload["sha256"], pkg, pkg)
    cabs += list(get_msi_cabs(data))

  # download .cab files
  for pkg in cabs:
    payload = first(sdk_pkg["payloads"], lambda p: p["fileName"] == f"Installers\\{pkg}")
    download_progress(payload["url"], payload["sha256"], pkg, pkg)

  print("Unpacking msi files...")

  # run msi installers
  for m in msi:
    subprocess.check_call(["msiexec.exe", "/a", m, "/quiet", "/qn", f"TARGETDIR={OUTPUT.resolve()}"])
    (OUTPUT / m.name).unlink()


### versions

msvcv = list((OUTPUT / "VC/Tools/MSVC").glob("*"))[0].name
sdkv = list((OUTPUT / "Windows Kits/10/bin").glob("*"))[0].name


# place debug CRT runtime files into MSVC bin filder (not what real Visual Studio installer does... but is reasonable)

redist = OUTPUT / "VC/Redist"

if redist.exists():
  src = redist / "MSVC" / msvcv / "debug_nonredist"
  for target in targets:
    for f in (src / target).glob("**/*.dll"):
      dst = OUTPUT / "VC/Tools/MSVC" / msvcv / f"bin/Host{host}" / target
      f.replace(dst / f.name)

  shutil.rmtree(redist)


# move msdia140.dll file into MSVC folder

msdia140dll = {
  "x86": "msdia140.dll",
  "x64": "amd64/msdia140.dll",
  "arm": "arm/msdia140.dll",
  "arm64": "arm64/msdia140.dll",
}

dst = OUTPUT / "VC/Tools/MSVC" / msvcv / f"bin/Host{host}"
src = OUTPUT / "DIA%20SDK/bin" / msdia140dll[host]
for target in targets:
  shutil.copyfile(src, dst / target / src.name)

shutil.rmtree(OUTPUT / "DIA%20SDK")


### cleanup

shutil.rmtree(OUTPUT / "Common7", ignore_errors=True)
shutil.rmtree(OUTPUT / "VC/Tools/MSVC" / msvcv / "Auxiliary")
for target in targets:
  for f in [f"store", "uwp", "enclave", "onecore"]:
    shutil.rmtree(OUTPUT / "VC/Tools/MSVC" / msvcv / "lib" / target / f, ignore_errors=True)
  shutil.rmtree(OUTPUT / "VC/Tools/MSVC" / msvcv / f"bin/Host{host}" / target / "onecore", ignore_errors=True)
for f in ["Catalogs", "DesignTime", f"bin/{sdkv}/chpe", f"Lib/{sdkv}/ucrt_enclave"]:
  shutil.rmtree(OUTPUT / "Windows Kits/10" / f, ignore_errors=True)
for arch in ["x86", "x64", "arm", "arm64"]:
  if arch not in targets:
    shutil.rmtree(OUTPUT / "Windows Kits/10/Lib" / sdkv / "ucrt" / arch, ignore_errors=True)
    shutil.rmtree(OUTPUT / "Windows Kits/10/Lib" / sdkv / "um" / arch, ignore_errors=True)
  if arch != host:
    shutil.rmtree(OUTPUT / "VC/Tools/MSVC" / msvcv / f"bin/Host{arch}", ignore_errors=True)
    shutil.rmtree(OUTPUT / "Windows Kits/10/bin" / sdkv / arch, ignore_errors=True)

# executable that is collecting & sending telemetry every time cl/link runs
for target in targets:
  (OUTPUT / "VC/Tools/MSVC" / msvcv / f"bin/Host{host}/{target}/vctip.exe").unlink(missing_ok=True)


### setup.bat

for target in targets:

  SETUP = f"""@echo off

set ROOT=%~dp0

set MSVC_VERSION={msvcv}
set MSVC_HOST=Host{host}
set MSVC_ARCH={target}
set SDK_VERSION={sdkv}
set SDK_ARCH={target}

set MSVC_ROOT=%ROOT%VC\\Tools\\MSVC\\%MSVC_VERSION%
set SDK_INCLUDE=%ROOT%Windows Kits\\10\\Include\\%SDK_VERSION%
set SDK_LIBS=%ROOT%Windows Kits\\10\\Lib\\%SDK_VERSION%

set VCToolsInstallDir=%MSVC_ROOT%\\
set PATH=%MSVC_ROOT%\\bin\\%MSVC_HOST%\\%MSVC_ARCH%;%ROOT%Windows Kits\\10\\bin\\%SDK_VERSION%\\%SDK_ARCH%;%ROOT%Windows Kits\\10\\bin\\%SDK_VERSION%\\%SDK_ARCH%\\ucrt;%PATH%
set INCLUDE=%MSVC_ROOT%\\include;%SDK_INCLUDE%\\ucrt;%SDK_INCLUDE%\\shared;%SDK_INCLUDE%\\um;%SDK_INCLUDE%\\winrt;%SDK_INCLUDE%\\cppwinrt
set LIB=%MSVC_ROOT%\\lib\\%MSVC_ARCH%;%SDK_LIBS%\\ucrt\\%SDK_ARCH%;%SDK_LIBS%\\um\\%SDK_ARCH%
"""
  (OUTPUT / f"setup_{target}.bat").write_text(SETUP)

print(f"Total downloaded: {total_download>>20} MB")
print("Done!")

File "C:\Users\root\Downloads\ep_portable\portable-msvc\portable-msvc.py", line 282, in <module>
    subprocess.check_call(["msiexec.exe", "/a", str(msi), "/quiet", "/qn", f"TARGETDIR={d2}"])

- @valinet at https://gist.github.com/mmozeiko/7f3162ec2988e81e56d5c4e22cde9977?permalink_comment_id=5053578#gistcomment-5053578

hi! it says line 282, and those seem to be the same lines where i faced this issue.
the fixes for those are absorbed already. check if you are using the latest version of this gist.

see the revisions to this gist. it says "revision from last week" github ain't showing any date 🤦

https://gist.github.com/mmozeiko/7f3162ec2988e81e56d5c4e22cde9977/revisions

Protip - you can switch Embed on top right of page to Clone and then use that URL to do git clone. Then getting updates will very easy - simply doing git pull will get you latest version of code.

@goyalyashpal Nah, I am using the latest version and get error 1603, while you got 1619. It is definitely something else, I don't know exactly what. I am running OS build 19044.4291 (LTSC 2021), have checked out d6d965ec296832941a83d512eed057d88552dd36. Whatever, I can patch it on my end just fine...

That sounds like some kind of per-requisite of msi package is missing. After Python script fails, run the msiexec command manually with extra arguments to produce log file - and check log.txt it produces for more detailed error messages:

msiexec.exe /a c:\path\to\downloads\crtd\vc_RuntimeDebug.msi /quiet /qn TARGETDIR=c:\path\to\temp /L*vx! c:\path\to\log.txt

msiexec.exe does the same thing (well with many extras which I don't care about).

But they both use same API - MSI Installer api. Here: https://learn.microsoft.com/en-us/windows/win32/msi/installer-function-reference
I am just too lazy to write all the usage code for it, so instead used msiexec directly - it should be always present on windows installation.

I'm struggling to get this to work with vcpkg, since it looks for a Visual Studio instance. Any idea what could be done?

-- Running vcpkg install
error: in triplet x64-windows: Unable to find a valid Visual Studio instance
Could not locate a complete Visual Studio instance

the msiexec.exe calls at lines 282 and 301 should both do a d2.resolve() instead of a straight d2. It failed trying to access a network location for me if I didn't.

I'm confused about that. d2 is already full path, it's not Path object. It is TemporaryDirectory when formatted to string gives you full path based on relative path to "downloads" folder. How do you get them to be network location?

it wasn't a full path for me, doing a print(f" dir: {d2}") in there printed out just dir: downloads\tmpi_xgyz8z without the preceding path. That got interpreted as a network location somehow by msiexec.exe (probably because of how my company setup it's network).

Doing a resolve fixed that.

Pushed an update. I think it should fix this.

I'm getting an error

Unpacking msi files...
vc_RuntimeDebug.msi ... 100%
cab1.cab ... 100%
VC_diasdk.msi ... 100%
cab1.cab ... 100%
Traceback (most recent call last):
  File "C:\Users\cairn\Desktop\test\portable\portable-msvc.py", line 329, in <module>
    shutil.rmtree(OUTPUT / "Windows Kits/10/Lib" / sdkv / "ucrt" / arch)
  File "C:\Users\cairn\AppData\Local\Programs\Python\Python310\lib\shutil.py", line 749, in rmtree
    return _rmtree_unsafe(path, onerror)
  File "C:\Users\cairn\AppData\Local\Programs\Python\Python310\lib\shutil.py", line 600, in _rmtree_unsafe
    onerror(os.scandir, path, sys.exc_info())
  File "C:\Users\cairn\AppData\Local\Programs\Python\Python310\lib\shutil.py", line 597, in _rmtree_unsafe
    with os.scandir(path) as scandir_it:
FileNotFoundError: [WinError 3] The system cannot find the path specified: 'msvc\\Windows Kits\\10\\Lib\\10.0.26100.0\\ucrt\\arm'

Pushed a fix. Seems latest Windows SDK v10.0.26100.0 removed 32-bit arm stuff.

@mmozeiko
I have a question about the x64/x86 selection of vc_RuntimeDebug.msi.
Is it for HOST or TARGET?

I'm trying for a HOST=x64 TARGET=x86 environment, (MSVC\14.40.33807\bin\Hostx64\x86)
Thus, in my opinion, vc_RuntimeDebug.msi (chip=x86) should be extracted. Right?

Yeah, you're right. p["chip"] should be compared to TARGET, not HOST. I've pushed updated code.

Trying to download MSVC 14.39 but getting this error when running the script
FileNotFoundError: [Errno 2] No such file or directory: 'msvc\\VC\\Tools\\MSVC\\14.39.33519\\bin\\Hostx64\\x64\\Microsoft.VisualStudio.Utilities.Internal.dll'

Hi, I want to share a modification I did days ago on line 23 for those who need to use the script:
Line 23

TARGET = input(f"Target: x64, x86, arm or arm64 ? ")
if not TARGET:
  TARGET = "x64"

That way can be selected different targets; when input field is empty, it set default value (x64).
I don't know python, but that was obvious and worked. However, it would be better if were added numbers to the options (1=x64, 2=x86, etc) or something better. And also, show a list of the available SDK versions and selected them (1. 10.26100, 2. 10.22621, etc).
Cheers.

And also, show a list of the available SDK versions and selected them (1. 10.26100, 2. 10.22621, etc).
- @ hellishvictor at https://gist.github.com/mmozeiko/7f3162ec2988e81e56d5c4e22cde9977?permalink_comment_id=5107833#gistcomment-5107833

that was already available as CLI stdin option if i recall correct

SDK 26100 seems to be missing a lot of headers, now my projects fail to build complaining it cannot find "winapifamily.h"

Pushed an update that should fix it. It also allows host/target selection in CLI arguments.

that was already available as CLI stdin option if i recall correct

Thank you, I'll check it out !

Pushed an update that should fix it. It also allows host/target selection in CLI arguments.

The previous script worked like a charm, but this fix shows:

Traceback (most recent call last):
  File "C:\Python\Lib\urllib\request.py", line 1344, in do_open
    h.request(req.get_method(), req.selector, req.data, headers,
  File "C:\Python\Lib\http\client.py", line 1336, in request
    self._send_request(method, url, body, headers, encode_chunked)
  File "C:\Python\Lib\http\client.py", line 1382, in _send_request
    self.endheaders(body, encode_chunked=encode_chunked)
  File "C:\Python\Lib\http\client.py", line 1331, in endheaders
    self._send_output(message_body, encode_chunked=encode_chunked)
  File "C:\Python\Lib\http\client.py", line 1091, in _send_output
    self.send(msg)
  File "C:\Python\Lib\http\client.py", line 1035, in send
    self.connect()
  File "C:\Python\Lib\http\client.py", line 1470, in connect
    super().connect()
  File "C:\Python\Lib\http\client.py", line 1001, in connect
    self.sock = self._create_connection(
                ^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Python\Lib\socket.py", line 853, in create_connection
    raise exceptions[0]
  File "C:\Python\Lib\socket.py", line 838, in create_connection
    sock.connect(sa)
TimeoutError: [WinError 10060] Se produjo un error durante el intento de conexión ya que la parte conectada no respondió adecuadamente tras un periodo de tiempo, o bien se produjo un error en la conexión establecida ya que el host conectado no ha podido responder

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "C:\MSVC\portable-msvc.py", line 97, in <module>
    manifest = json.loads(download(URL))
                          ^^^^^^^^^^^^^
  File "C:\MSVC\portable-msvc.py", line 31, in download
    with urllib.request.urlopen(url, context=ssl_context) as res:
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Python\Lib\urllib\request.py", line 215, in urlopen
    return opener.open(url, data, timeout)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Python\Lib\urllib\request.py", line 515, in open
    response = self._open(req, data)
               ^^^^^^^^^^^^^^^^^^^^^
  File "C:\Python\Lib\urllib\request.py", line 532, in _open
    result = self._call_chain(self.handle_open, protocol, protocol +
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Python\Lib\urllib\request.py", line 492, in _call_chain
    result = func(*args)
             ^^^^^^^^^^^
  File "C:\Python\Lib\urllib\request.py", line 1392, in https_open
    return self.do_open(http.client.HTTPSConnection, req,
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Python\Lib\urllib\request.py", line 1347, in do_open
    raise URLError(err)
urllib.error.URLError: <urlopen error [WinError 10060] Se produjo un error durante el intento de conexión ya que la parte conectada no respondió adecuadamente tras un periodo de tiempo, o bien se produjo un error en la conexión establecida ya que el host conectado no ha podido responder>

I'm on Win 7 x64 SP1. And btw, thank you for the implementation of host/target selection in CLI arguments.

Windows error 10060 is connection timeout error. Either something is too slow on your network, ISP throttling you or timing out connections or DNS requests to some domains. Try opening URL directly in IE, if that does not work, then you need to solve that problem first. Otherwise if that does work then try increasing timeout in urlopen() call.