scotterman

notes to help me remember

Category Archives: Connectivity

Tray Icon Says No Internet When There Is!

SHORT ANSWER:

  • Uninstall network adapter in device manager
  • Scan for hardware changes to reinstall it
  • Wait a few minutes.

And more about it:

So, have been seeing this a lot lately, and am mildly annoyed by it.  Everything seems to be working, but the network icon in the system tray shows a yellow warning triangle with exclamation point (!).  Mousing over it shows the “no internet access” tool tip.  This isn’t a new issue.  I have seen it off and on for nearly as long as we have been using Windows 7.  Everything works, so no big deal you say.  Except that we have hundreds (OK, maybe dozens) of ever vigilant users who are spooked by every dire warning message they see on their computer.  (OK, maybe not every warning, they seem to blithely ignore the most significant messages of impending system failure.)

So, found some good discussion about the issue at the Microsoft Answers site here and here.  Granted, none of this really helped me understand why this might be happening, but I did get rid of the little yellow harbinger of doom at my own workstation.  A minute or two after I uninstalled and reinstalled the network adapter in Device Manager the network icon reverted to its correct, happy self, “internet access”.

No Internet Connection (Wired or Wireless)

Had a laptop that would not connect to the internet.  Either wired or wirelessly it would not be able to get an IP address from DHCP.  I found this in the helpful Microsoft knowledgebase article 817571 (http://support.microsoft.com/kb/817571).  Essentially, the Windows sockets registry subkeys have become corrupted and must be replaced:

Method 1 exports the subkeys, then recreates them, other methods involve copying the keys from an operational, similar computer.

Use Registry Editor to export and delete the Winsock and Winsock2 registry subkeys, and then remove and reinstall TCP/IP on Microsoft Windows 2000 or  Microsoft Windows XP.   To do this, follow these steps.

Export and delete the corrupted registry subkeys

  1. Insert a floppy disk in the floppy disk drive of the computer whose registry entries you are exporting.
  2. Click Start,  click Run, type regedit,  and then click OK.
  3. Locate and then click the following registry subkey:
    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Winsock
  4. Do one of the following steps, depending on the operating system:
    • For Windows XP, on the File menu, click Export.
    • For Windows 2000, on the Registry menu, click Export.
  5. In the Save in box, click 3½ Floppy (A:), type a name for the file in the File name box,  and then click Save.
  6. Right-click Winsock, and then click Delete. When you are prompted to confirm the deletion, click Yes.
  7. Repeat steps 3 through 6 for the following subkey:
    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Winsock2

    Note Each  .reg  file that you save must have a different name.

  8. Right-click Winsock2, click Delete, and then click Yes.
  9. Quit  Registry Editor.

Windows XP-based computer

Reinstall TCP/IP on a Windows XP-based computer

In Windows XP, the TCP/IP stack is a core component of the operating system. Therefore, you cannot remove TCP/IP in Windows XP.

  1. Install TCP/IP on top of itself. To do this, follow these steps:
    1. In Control Panel, double-click Network Connections, right-click Local Area Connection, and then click Properties.
    2. Click Install.
    3. Click Protocol, and then click Add.
    4. Click Have Disk.
    5. In the Copy manufacturer’s files from box, type System_Drive_Letter:\windows\inf,  and then click OK.
    6. In the list of available protocols, click Internet Protocol (TCP/IP), and then click OK.
  2. Restart your computer.

This did the trick for me.  I needed to reinstall the TCP/IP for both the LAN and wireless connections.

Wi-Fi in Windows 7

I may have posted about this, but, alas, I can’t remember (the whole point of this blog, I guess).  To keep Windows 7 (I suppose it may be the same in other Windows versions as well) from shutting off the wireless when “not it use”, do the following from a Tom’s Hardware forum:

Navigate to the control panel and open the Device Manager. Open the Network adapters section, right-click your wifi adapter and choose Properties. Navigate to the Power Management tab, uncheck allow the computer to turn off this device and set it to allow this device to wake the computer and then save the changes you made.

Alternatively, click on the wireless icon in the system tray and open the Network and Sharing Center.  Click on the wireless connection, click on Properties and then Configure.  Select Power Management and uncheck “Allow the computer to turn off this device to save power”.

Dis-allowing this is helpful in ensuring that students don’t lose their work when editing files from the file server.

Finding that MAC Address

Blocking devices by MAC address again in order to preserve sanity.  Some people, however, need access for their device.  A quick guide to finding those MAC addresses:

Original Kindle  (from technipages)

  1. From the Home screen, press Menu
  2. Select Settings
  3. The Wi-Fi MAC Address is located toward the bottom of the screen in the Device Info section

Kindle Fire (from Overton County Schools)

  1. From the home screen, tap on “Settings” in the top right corner
  2. Tap on “More”
  3. Tap on “Device” in the “Settings” Page
  4. MAC address is listed as “Wi Fi Mac Address”

iPad (from iPad to PC)

  1. Select the settings icon
  2. Tap “General” and then “About”
  3. The MAC address is listed as “Wi-Fi Address” (format xx:xx:xx:xx:xx:xx)

Windows (from custhelp.com)

Windows 7 / Vista

  1. Click the Wireless Network Connection icon from within your system tray (near the clock).
  2. Select Network and Sharing Center.
  3. Select View status.
  4. Select Details.
  5. The MAC address is listed as Physical Address:

Windows XP/2000

  1. Click on Start and click on Network Connections on the right side of the menu
  2. Double-click on Local Area Connection (to find the MAC address of wired adapter) or Double-click on Wireless Adapter (to find the MAC address of the wireless adapter), or if you have a wireles connection icon in your system tray you can double-click on it!
  3. Click on the “Support” tab
  4. Click on “Details”
  5. The MAC address is the Physical Address (format is xx-xx-xx-xx-xx-xx)

MAC Address Filtering on Server 2003

I was just looking at one of my posts from last March about mobile lab connectivity. One thing I can add is that we set our lab laptops so that Windows cannot turn off the wireless. This way students are less likely to lose their network connection once they get one. We have also greatly increased the number of access points in the buildings (which has led to new issues with wireless interference and channel selection).

I wanted to add the link for MAC address filtering on Server 2003. Despite doubling the number of addresses available, we have again started to run out occasionally at one location. Blocking DHCP access to non district computers using MS Callout Filter is discussed here.  Found the download and instructions here on Mark M Manning’s blog. Thanks Mark!

Windows 7 TCP Auto-tuning and Server 2003

For most of the year we have been dealing with slow, unreliable connection to our network.  We have Windows Server 2003 for our file server and domain, and mostly Win XP clients, with a few Windows 7.  We have one mobile lab running Windows 7, and a couple of other computers running it as well.

We eliminated several problems this year including blocking DHCP access to non district computers using MAC callout filtering.  Sorry, I can’t remember, offhand, where we found it, but the download and instructions are readily available.  We replaced our “older than the hills” switches, as well as our access points.  The APs were not old, but not as beefy as the replacements, and not all configured the same.  All in all, very good improvements for the year.  We will be replacing our file server in the near future.

But with all the upgrades and changes, one thing has remained constant: poor connectivity to the network.  Students have been able to log on to the network, but then can’t access the file server, or their files don’t open, or worst of all, they can’t save their work.  The connections just seem to time out, or go to limbo.  Mind you, this doesn’t always happen, and almost never when trying to replicate the issue on one machine.  It became clearer that the issues seemed to be mostly affecting the mobile lab running Windows 7.

Research has pointed to Windows 7 TCP auto tuning as a possible suspect.  These articles all discuss auto tuning:

Microsoft Technet Forums
Sevenforums
SpeedGuide (several tweaks for connectivity)
Microsoft Knowledgebase (slow file transfers)

I opened the command window and executed the following commands on the Windows 7 mobile lab computers:

netsh int tcp set heuristics disable
netsh int tcp set global autotuninglevel=disable

The first command turns off the Windows 7 automatic override for TCP settings, and the second turns off the autotuning.  The post by canspec on Seven Forums speaks most directly to this issue.  The other links above include other possible reasons for connection problems.

However, this did not seem to be related to our issues.  Perhaps more significant were making sure that the Windows did not shut off the wireless when not in use (under power management in properties for the wireless controller) , and that automatic caching of files is turned off.

Accessing the iTunes store through a firewall/filter

Needing to access iTunes again, which we struggled to block last year with our bandwidth issues.  Seems I slogged through the Apple site for quite a while last time looking for their little list of sites (servers) that need to be open/blocked to allow/deny access.  Once again I have frittered away time looking for that little list.  Found it here (http://support.apple.com/kb/TS3125):

IMPORTANT: iTunes must be allowed to contact Apple using the following ports and servers:

  • port 80
  • port 443
  • phobos.apple.com, deimos3.apple.com, albert.apple.com, gs.apple.com, itunes.apple.com, ax.itunes.apple.com

For a more complete list of ports used by Apple products see “Well known” TCP and UDP ports used by Apple software products

 iTunes also contacts VeriSign servers during an iPhone restore and activation:

  • evintl-ocsp.verisign.com
  • evsecure-ocsp.verisign.com

By the way, the list of “well known TCP and UDP ports used by Apple software products” is quite impressive and voluminous. Just to make it a little easier to see, the servers used are:

phobos.apple.com
deimos3.apple.com
albert.apple.com
gs.apple.com
itunes.apple.com
ax.itunes.apple.com

Locating a Device by IP Address

IP address conflicts pop up here and there, sporadically.  Sloppiness borne of haste on our part, outside devices on our network, or the occasional access point that resets to its defaults.  These can all lead to IP address conflicts.  These are generally just an annoyance, and don’t result in any difficulties.  Tracking them down can be frustrating and not worth the effort.  But I recently got a little frustrated with a persistent conflict and decided to find a tool to help track it down.  I found a handy little utility called Zenmap (ver 5.51) that provides a handy GUI for Nmap.   Available from Nmap.org, this utility spits out useful information gleaned from the item connected to the network at the IP address you enter into the program.  It can show info about the type and name of the device that help identify what is causing an IP conflict on the network.  Helped me find the wireless access point that I had set up with a static IP and no reservation in DHCP (sloppiness, as I said).  Zenmap was kinda fun to use, and other than the single eye logo for the program, I am pleased with it.  (Not so much the logo, just not a favorite of mine.)

I’m Trying to Join the Domain!

Routine setup of a couple of late entries to the new computer line-up for this year.  Doing the final stuff before turning them over to the expectant users.  You know, join the domain, add printers, put a few desireable links on the desktop, etc.  Whoops, donk!, Windows 7 informs me in a mildly verbose message:

Computer Name/Domain Changes

The following error occurred attempting to join the domain “nnnn”:

An attempt to resolve the DNS name of a domain controller in the domain being joined has failed.  Please verify this client is configured to reach a DNS server that can resolve DNS names in the target domain.  For information about network troubleshooting, see Windows Help.

OK, Google time.  Several sites advise to manually set the DNS IP address in the IPv4 settings, join the domain, then reset the settings to what they should be.  Not wanting to trek over to the server to figure out what the proper DNS IP address is, I try one or two most likely suspects, have no luck, run out of time, and go home for the weekend.

Back to it the following week, I again Google the error, find the same advice, and also one helpful comment that seems so obvious.  Someone, somewhere (may have been a Tom’s Hardware forum), mentions that you may put the correct information in the DHCP settings.  Well, of course!  Why is it that the obvious solution (as well as the best one) so often eludes me.  Taking a look to find the IP address for the DNS, I realize why the poor computer was having a problem.  I decided to leave the straightening out of that situation to someone more informed than me, but I did locate an appropriate IP address for a DNS.  I plugged it into the TCP/IP properties and joined up with the Domain.

Identifiying blocked sites

Downloaded and installed MS Network Monitor 3.4 to identify what web site was being blocked for glogster.com, causing pages to not fully load (flash animations would not load, had a spinning pink donut).

Network monitor was able to show what traffic was going across Internet Explorer on my PC, then I could identify which site was blocked.

Network monitor download file was NM34_x86.exe, also has versions for Windows 7 and 64 bit.