August 2016

Excel: Check email addresses in bulk if format is correct or not

So had a request today to clean up email addresses as some of them were not valid. This was needed for over 1500 email addresses.

So used the formula below and was able to find all addresses that were “FALSE”. I filtered them out and was able to fix them as needed.

Here’s what you need to do:

If your e-mails are in A column, go in the B column and in the B1 cell and copy paste this code:

Then, go down and left on the B1 cell so you can copy and paste the code to the other cells.  For all the valid e-mails, it will give you ‘TRUE’ and for the invalid ‘FALSE’.


DFS Namespace service could not initialize cross forest trust information

After you install Active Directory on Windows Server 2008 R2, you may start seeing the following error message after the server boots:

The DFS Namespace service could not initialize cross forest trust information on this domain controller, but it will periodically retry the operation. The return code is in the record data.

This occurs because the DFS Namespace service attempts to access Active Directory before it has completely initialized.
To resolve this issue, we simply have to force the DFS Namespace service to start after the Active Directory service has initialized. We can do this by setting the DFS Namespace service to depend on the Active Directory service as well as setting it to a Delayed Startup mode.

To make those changes, start regedit and make the following changes :

  1. Navigate to the registry key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\Dfs
  2. Modify the DependOnService value and add NTDS to the list.
  3. Create a new DWORD value named DelayedAutostart and set its value to 1.

DNS broken after Windows Update KB3145126

I noticed the DNS broke on my servers after Windows Update.

The problem was KB3145126. Read more about it here.

After a quick removal and reboot, DNS was operational again.

To remove/uninstall KB3145126, open powershell and run the following:

Hope this helps.

Check Proxy settings from Powershell

To check the proxy settings like ProxyOveride or if it is enabled or not:

To disable proxy from PowerShell:

To enable proxy from PowerShell:


IE Enable/Disable Proxy Settings via Registry

Whatever the reason may be to enable or disable proxy, here is a simple registry hack to turn it on or off.

Open powershell in admin mode.



The above method require an IE restart, alternatively if you don’t want to restart IE. Make similar change under:

To find your SID read here.

Disable IPv6 on Windows Core Server 2008 R2 – 2012 R2

GUI Version:


  1. Open Control Panel > Network & Internet > Network & Sharing Center > Change Adapter Settings > Choose the Adapter
  2. Right Click – Select Properties
  3. Networking Tab
  4. DeSelect IPv6
  5. Close

No GUI… No problem (Core):

After doing the above procedure you might have to use the registry editor aswell to completely disable the ipv6 tunnel

Here’s what to do to disable IPv6 on Core Windows Server

First check the interface that you want to disable.


To completely disable IPv6 on a Windows Server 2008/2012-based computer yourself, follow these steps:

    1. Open Registry Editor.
    2. Locate the following registry subkey:
    3. In the details pane, click New, and then click DWORD (32-bit) Value.
    4. Type DisabledComponents, and then press ENTER.
    5. Double-click DisabledComponents, and then type 0xffffffff in Hexadecimal or 4294967295 in Decimal.Note The 0xffffffff value or the 4294967295 value disables all IPv6 components except for the IPv6 loopback interface.

      Also we can try this command to Disable IPv6 in Windows

    6. Reboot
    7. Re-run the above command to see if the interface shows IPv6 addresses