Check Whether the Exchange Server is an Open SMTP Relay using a Telnet Test

A Telnet test involves establishing a Telnet session from a computer that is not located on the local network to the external (public) IP address of the Exchange server. You need to carry out the test from a machine at home, or from another office. Doing the test from a machine on your own network will produce useless results.

  1. Start a command prompt.
    Either click start, run and type CMD
    or Choose Command Prompt from Start, Programs, Accessories, Command Prompt
  2. Type “telnet” (minus quotes) and press enter.
  3. At the Telnet prompt, type

    set localecho

    (minus quotes) and press enter. This lets you see what is going on.

  4. Still in the telnet prompt, enter the following command and then press enter

    open external-ip 25

    where external-ip is your external IP address eg:

    open 111.222.333.444 25

  5. You should get a response back similar to the following:

    220 mail.server.domain Microsoft ESMTP MAIL Service, Version: 6.0.2790.0 Ready at

  6. Type the following command in to the telnet windows:


    and press enter (note “” can be anything that isn’t a domain that the Exchange server is responsible for.

  7. After pressing OK you should get a response back

    250 OK

  8. Type the following command in to the telnet window:


    and press enter (again where address@testdomain is an email address that is not on the Exchange server. Note the lack of space between from and the first part of the address).

  9. After pressing OK you should get a response back:

    250 2.1.0….Sender OK

  10. Type the following command in to the telnet window:


    and then press enter (where is not either an address you use internally or the address you entered earlier as the from. Once again note the lack of space between to and the first part of the e-mail address).

  11. After pressing enter you will get one of two responses.
    If you get

    550 5.7.1 Unable to relay for

    then you are relay secure.
    However if you get

    250 2.1.5

    Then you are an open relay.

If you are synchronizing an Office 365 account with an on-premises Active Directory, you know that you cannot edit exchange user properties using the Office 365 administrator portal.  In this article, I will show you how to add e-mail aliases using the Active Directory Service Interfaces Editor (adsiedit).

  1. Go to Start > Run and type adsiedit.msc
  2. Now, find the unit where your AD user’s reside
  3. Right click the user you want to edit and click Properties.
  4. Find the variable proxyAddresses – this is the one you want to edit.
    When you add new e-mail aliases, you want to make sure that your primary e-mail address will start with upper-case SMTP. Your aliases, aka, secondary addresses should be lower-case smtp.For example, I want my primary e-mail address to be
    In the proxyAddresses attribute, I would put:
    As my alias, I want… to do this, I will use lower case smtp:

Apply the new settings and wait for your active directory to be synchronised with Office 365 (by default this happens every 3 hours)

Installing Dell OMSA on a ESXi server allows you to see more detailed information regarding the Dell hardware. It also allows you to perform operations such as specifying hot spares and rebuilding RAID arrays. After you install OMSA on the ESXi server you can install the OMSA web-based GUI on another Windows PC or Server in order to access OMSA.

The steps below will get OMSA up and running on VMWare ESXi 5.5. Be sure to download the version of the OMSA Offline Installation Bundle that corresponds to your version of ESXi.

Download the OMSA Offline Bundle from the Dell Website.
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Open gpedit.msc and browse to the location /Computer Configuration/Administrative Templates/System/Internet Communication Management/Internet Communication Settings and double click “turn off access to all windows update features” and set it to disabled.
Open regedit and back up the key

Remove reg key from regedit
and delete WindowsUpdate as it may contain your administrator settings for windows update which  includes a WSUS server address, this entry prevents your windows update from contacting windows update directly.


Windows Server Time Sync Configuration

The following steps can be used to configure DCs the default Windows time service hierarchy in an AD forest.  The procedure will also remove any errors in the Event Viewer, if any existed.

Do not use if you are using a third party stratum service and refer to the vendor’s documentation for further instructions

Check and Document the Current Time Configuration on the PDC Emulator
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Windows 2012 R2 currently halts with an error (0XC000000F)  when the Windows Deployment Server attempts to Capture an Image.  Run the below commands to mount the capture wim file and then unmount.  This work around will allow WDS to run and capture the image
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