MSD Chemstation won't open - message "in use by another session"

Cannot get MSD Chemstation to open - get a message "Mass Spec is already in use by another session".  Version G1701EA E.02.02.1431 / WIN 10 operating system.  System was shut down temporarily and on startup,  the software does not open.  It is an Agilent 5975MS with a 6890N GC.  Tried rebooting the controller on the MS itself, but that did not work.  Also looked at binding order, but possibly did not do that correctly.  Both MS and GC can be pinged successfully from the PC.  Does anyone know what might be wrong?  Thanks

  • Hello ,

    "in use by another..." is a safety function that prevents a second session to the MSD: OK & wanted function.


    1st) troubleshooting
    because a PING does only a small (OSI) communication check (are voltages & cabling OK?), I recommend the communication check via internet browser (IE, chrome...)

    if this step failed:
       * check LAN card settings
       * check / modify proxy settings
       * remove 2nd LAN card (domain network)
       * check firewall settings



    2nd) step if check (1) was OK => only a MSD power off/on will help

       note: with older 5973 MSDs, the MS must still receive an IP via BootP after the power cycle


    regards, M.

  • 1) do you see the orange screen? If so, the basic communication should work.


    2) next step: create a 2nd instrument (maybe without GC) & start instrument


    3) was something changed by your IT department?

      e.g. new safety policy? new firewall? new windows 10 updates?

      BTW: which Windows 10 version is installed? e.g. (19.03, 2004)

  • BTW: "Mass Spec is already in use by another session"


    can be caused by a wrong LAN card binding/priority. unfortunately this cannot be easily changed in Win10, the most efficient setting would be a low 'metrics' in the IP settings.

    Please remove the domain LAN cable & additionally restart Windows.

  • Hello tdnola, 

    1) LAN card bindings:

          this is only important if more than one LAN card is in use.

          I hope there is no other LAN connected? (e.g. charge your mobile phone on the PC & hotspot is activated).

          Since you have removed all unneeded cables you do not need to worry about bindings & metrics


    2) metrics: I would ask your IT department about this.

          Google search: lan card metrics windows 10

          Here windowscentral page is helpful.


    3) you could possibly upload your ACQ Start LOG here. Maybe we can see something inside.

    For G1701: c:\msdchem\MSexe\icstart1.log  (where 1 is the instrument no.)

  • LAN card priorities (by InterfaceMetric)

    To check the order of all LAN cards (here metric based) I use a powershell line.

    The complete blue command must be in ONE powershell line

    Get-NetIPInterface | select ifIndex,InterfaceAlias,ConnectionState,InterfaceMetric,AutomaticMetric,Dhcp,AddressFamily | sort InterfaceMetric, ifIndex | FT -autosize



    Example of PowerShell command and its output for one NiC:


    The lower the (Interface)Metric number, the higher the LAN card (NiC) priority.

  • Hi tdnola,

    This is a smart card that thinks its already being controlled by a Chemstation. The most common and quickest fix is to restart(power cycle) the MSD which will clear the lock. I usually like to restart the system rather than just one module. Its worth noting that the version of Chemstation you are using is not a supported solution on the Windows 10 platform.



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