When Windows automatic update suddenly stops updating Windows automatically

Recently we noticed that some of our test and dev servers were not updating automatically through Windows or Microsoft update.

It was real pain to find why this happened. There are numerous threads in the Internet about failed Windows update, and it is very hard to find the right answer. Luckily, I found a post in CNET forum from Jim Sheehy from Sequel Data Systems. He supports more than 800 desktops and he is writing about three possible causes of Windows update failure:

  1. The Windows Update Temporary folder is corrupted. (%windir%\SoftwareDistribution)
  2. Update Agent 3.0 is not installed properly. (Download latest Update Agent)
  3. Installer 3.1 is corrupted. (Reinstall Windows Installer 3.1 or …)

Read more at CNET forum: Help! My Windows automatic updates suddenly stopped working.

Strange MAC addresses in your network (00:0D:3A:D7:F1:40 – 00:0D:3A:FF:FF:FF)

Today I noticed many strange MAC addresses in our LAN. The addresses looked very similar – only few bits were changing. Sometime this happens, when Ethernet cable is damaged or due to network card malfunction. Here are some sample MAC addresses I observed:

  • 000d3a-fa6109
  • 000d3a-fa6207
  • 000d3a-fa6209
  • 000d3a-fa6107
  • 000d3a-fa6203
  • 000d3a-fa6103
  • 000d3a-fa6212
  • 000d3a-fa6112
  • 000d3a-fa610f
  • 000d3a-fa620f

It turns out, that this time these MAC addresses appeared because someone in our LAN clicked on See full map under Control PanelNetwork and Sharing Center.

Microsoft documentation about Link Layer Topology Discovery (LLTD) Protocol states that:

This protocol defines a range of special MAC addresses that applications can use when they conduct network topology tests. This range is 0x000D3AD7F140 through 0x000D3AFFFFFF. These MAC addresses do not conflict with actual MAC addresses because the range is built from an assigned Organizationally Unique Identifier (OUI)…

Read more here:
http://www.microsoft.com/whdc/connect/rally/lltd-spec.mspx
http://download.microsoft.com/download/a/f/7/af7777e5-7dcd-4800-8a0a-b18336565f5b/LLTD-spec.doc