vSphere 5.5 Client and WindowsXP/Windows2003 – Unknown Connection Error

19 Oct

If you try to install the new vSphere5.5 C# Client to WindowsXP/Windows 2003, you will receive warning during the installation of possible problems. The problems is caused by the lack of support for some SSL ciphers on Windows XP and Windows Server 2003. Although the install will succeed and you’ll be able to connect to vSphere5.1 (and older) ESX hosts, if you attempt to connect to a vSphere5.5 host then you will receive this error message:

An unknown connection error occurred. (The Client could not send a complete request to the server. (The underlying connection was closed: An unexpected error occurred on a send.

The actual error looks like this:

Screen Shot 2013-10-19 at 12.56.28

There is a fix but only for Windows 2003 and WindowsXP 64-bit. This means Windows 2003 and XP 32-bit clients cannot use the ye olde vSphere Client. That’s was my situation so the fix wouldn’t install for me…

The link for the fix is below. It’s one of those where you have to supply an email, and then they email you a link to the hotfix. I’m assuming that’s so Microsoft and track and trace those people who need the fix.

It’s also worth mentioning that the vSphere Client no longer installs to a Windows system running the Domain Controller role:

Screen Shot 2013-10-19 at 18.33.41


Posted in vSphere


Leave a Reply


  1. random person

    October 20, 2013 at 8:17 pm


    Have you found any workaround for this issue? I just upgraded from esxi 5.1 to 5.5 and am running XP Tablet 32 bit so…. I’m a bit stuck :u

  2. richardvm

    October 30, 2013 at 11:43 pm

    For those that don’t have vCenter or want to connect to a stand alone ESXi 5.5 host via the vSphere Client, you’ll need to ssh into the ESXi host and modify the following file: /etc/vmware/rhttpproxy/config.xml

    Insert the following xml line into the appropriate section:


    After saving your changes restart the service:
    /etc/init.d/rhttpproxy restart

    Hope this helps.

    • sam

      November 6, 2013 at 11:59 am

      I’ve followed this KB article as well as help from all the above people :)
      This works for vmware client trying to access ESXi 5.5 with XP 32 bit. I edited /etc/vmware/rhttpproxy/config.xml with vi and added the lines

      to the section at the bottom, and restarted the rhttpproxy as richardvm says.
      Thanks for the help all. Don’t have to upgrade just yet ;)

      • sam

        November 6, 2013 at 12:00 pm

        I added the lines

        ” 120000

        The html of the post took the brackets out so… check out the KB article for exact details.

        • Pete

          November 27, 2013 at 8:22 am

          Hi. Has anyone come across a fix yet for vcenter 5.5 and XP x86, for the C# client?

          One thing I plan on doing is using the Boomerang fling, seems to work OK for just connecting to VM’s

          • Mike Laverick

            November 27, 2013 at 10:35 am

            I think if you look at the comments on the post – there are number of people who have responded with work arounds… Although personally, I think it might be time to leave Windows XP/2003 behind. Support (not just for VMware technologies) is only going to get harder than easier from this point onwards…

          • Pete

            December 2, 2013 at 2:52 pm

            I think you may be right Mike, unfortunately some of places where I work are living in the stone age when it comes to their desktop environment :-) In those cases I’ll Boomerang to a Win7 VM or just learn the Web Client :-)

          • Mike Laverick

            December 2, 2013 at 8:48 pm

            Yep. I hear ya. I know what you mean – even in my lab environment I had an ye olde 2003/Citrix/Presentation Server that I found I couldn’t run the client on. Fortunately, I’d moved over to a PCoIP/View environment with Win7 desktop…

        • Terence

          February 6, 2014 at 10:01 am

          What section is that?

        • Terence

          February 6, 2014 at 10:01 am


          what section are you referring to?

  3. Paul Sheard

    December 9, 2013 at 1:18 pm

    I’m running vCenter 5.5 and ESXi 5.5 hosts.

    My Macbook is running Fusion and a Windows 7 32bit VM. I can connect to vCenter without a problem, but when I try and install the SRM plugin I get the error described in Mikes post…

  4. H Banks

    December 30, 2013 at 3:34 am

    You Sir, I owe a Drink! I’ve banged my head on this issue on two different VM guests and several browsers. That was half a day I wish I would have read this earlier.

  5. M Milller

    July 28, 2014 at 7:57 pm


    Just as an fyi, there is a 32bit version of this fix available for Windows 2003. shows this. Not sure if the patch will apply to Windows XP, however.

    Hope this helps!

    • Peter

      August 5, 2014 at 9:57 am

      I tested the hotfix for Windows 2003 (manually installed it on my XP 32 bits) – it does not work. It seems that there is no solution for XP 32 bits.

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