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Proxy-Trouble

Jump To: Support > KB > NetManager > Proxy > Trouble

NetManager webproxy - A few common issues

Doesn't seem to be working at all

Symptoms: Error messages in browser, but the messages don't come from the NetManager

Check your computer can speak to the NetManager. You could do this by going to a command prompt and typing ping netmanager.

Check that the proxy is running, go to System > Services? in webadmin and check that the Web Proxy service is running.

Always getting access denied or some random program cannot connect

Check the port number of your request. The web address (URL) will look something like https://address.of.site:port/other/stuff/. If there is colon followed by a number in the address, it may be using a non-standard port. These are blocked by default as it would be very easy to use such a thing to reduce your network security.

If the request is a standard web-request (i.e. begins with http:// the only ports you can connect to are:

  • 80 (HTTP)
  • 21 (FTP)
  • 443 (HTTPS)
  • 880 (NetManager webadmin)
  • 1025-65535 (general unreserved ports)

If the request is anything else (e.g. https:// or rtsp://), the proxy is being used as a gateway (or tunnel) to the outside with little filtering and thus it is imperative that only trusted ports are connected to. By default, the only port that can be connected to is 443 (HTTPS). Therefore if programs try to use your proxy to connect to the outside world you will be alerted to it by it being blocked. You can add extra ports to this list easily by going to Web-Proxy > Settings? in webadmin and clicking on the Allowed CONNECT ports tab.

Windows updates are failing

Firstly, check that you don't have any filters blocking Windows Updates. For details on this, see here.

On Windows Vista, 7, Server 2008 and Server 2008 R2 the proxy settings set for the user logged on are not used by Windows (or Microsoft) updates as the update process runs as a machine service rather than as the user. To fix this, use the netsh winhttp import proxy ie command:

C:\Users\administrator>netsh winhttp import proxy ie

Current WinHTTP proxy settings:

    Proxy Server(s) :  netmanager:3128
    Bypass List     :  <local>

To reset back to a direct connection:

C:\Users\administrator>netsh winhttp reset proxy

Current WinHTTP proxy settings:

    Direct access (no proxy server).

Similarly, on Windows 2000, XP and Server 2003, if Automatic Updates are enabled, the user's proxy settings are not used. Use the proxycfg -u to import the settings from the current user:

U:\>proxycfg -u
Microsoft (R) WinHTTP Default Proxy Configuration Tool
Copyright (c) Microsoft Corporation. All rights reserved.

Updated proxy settings
Current WinHTTP proxy settings under:
  HKEY_LOCAL_MACHINE\
    SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Connections\
      WinHttpSettings :

    Proxy Server(s) :  netmanager:3128
    Bypass List     :  <local>

To revert to a direct connection use proxycfg -d:

U:\>proxycfg -d
Microsoft (R) WinHTTP Default Proxy Configuration Tool
Copyright (c) Microsoft Corporation. All rights reserved.

Updated proxy settings
Current WinHTTP proxy settings under:
  HKEY_LOCAL_MACHINE\
    SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Connections\
      WinHttpSettings :

     Direct access (no proxy server).

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Page last modified on May 05, 2011, at 09:41 AM by sborrill