unable to run Grasshopper on Rhino4 under "User" account

Dear all,

I am having a problem loading a grasshopper 0.9.0014 on Rhino4 SR9

I have 2 users on my Windows 7 PC. Under "Admin" it loads ok, but under

"User" it gives this message as I type "grasshopper" in the command line in Rhino:

"Unable to load Grasshopper.dll plug-in: Rhino version not specified."

Details of the command line are as follows:

Command: Grasshopper
Rhino.NET plug-in: C:\Program Files\Rhinoceros 4.0\Plug-ins\Grasshopper\Grasshopper.dll
> - referenced assembly count: 20
>    - mscorlib
>    - Microsoft.VisualBasic
>    - System.Windows.Forms
>    - GH_IO
>    - System.Drawing
>    - System
>    - RhinoCommon
>    - GH_Util
>    - OpenTK.GLControl
>    - QWhale.Editor
>    - QWhale.Syntax
>    - QWhale.Syntax.Parsers
>    - System.Core
>    - System.Design
>    - System.Xml
>    - System.Data
>    - OpenTK
>    - QWhale.Common
>    - System.Xml.Linq
>    - System.ServiceModel
> Rhino.NET error: unable to locate a reference to Rhino_DotNET.DLL
> Unable to load Grasshopper.dll plug-in: Rhino version not specified.

I tried creating the new user and looks like that one works too, but I do need my current "user" profile as there are a lot of things already set up well, do not want to miss those.

If someone could advise me on where to look for the problem?

Thank you,

Artem