nop commerce 2.1 installation error. why ?

I download nop commerce 2.1 version from the link :
http://nopcommerce.codeplex.com/releases/view/69081#DownloadId=276390.
I build the entire project and also run Prepare.bat file. This process is ok , i get 0 errors message. Now I start to run Deploy.bat file , and shows one error occur.In the presentation folder i did n't change anything.

The error details will show below.


10>Done Building Project "C:\Users\admin\Desktop\nop20\Presentation\Nop.W
       eb.Framework\Nop.Web.Framework.csproj" (default targets).
    24>_CopyWebApplicationLegacy:
         Copying Web Application Project Files for Nop.Web
         Copying file from "obj\Debug\Nop.Web.dll" to "C:\Users\admin\Desktop
         \nop20\build\..\Deployable\nop_2.1\\bin\Nop.Web.dll".
    24>C:\Program Files\MSBuild\Microsoft\VisualStudio\v10.0\WebApplications\Mi
       crosoft.WebApplication.targets(131,5): error MSB3021: Unable to copy fil
       e "obj\Debug\Nop.Web.dll" to "C:\Users\admin\Desktop\nop20\build\..\De
       ployable\nop_2.1\\bin\Nop.Web.dll". Could not find file 'obj\Debug\Nop.W
       eb.dll'. [C:\Users\admin\Desktop\nop20\Presentation\Nop.Web\Nop.Web.cs
       proj]
    24>Done Building Project "C:\Users\admin\Desktop\nop20\Presentation\Nop.W
       eb\Nop.Web.csproj" (ResolveReferences;_CopyWebApplication target(s)) --
       FAILED.
     1>Done Building Project "C:\Users\admin\Desktop\nop20\build\nop.proj" (D
       eploy target(s)) -- FAILED.

Build FAILED.

       "C:\Users\admin\Desktop\nop20\build\nop.proj" (Deploy target) (1) ->
       "C:\Users\admin\Desktop\nop20\Presentation\Nop.Web\Nop.Web.csproj" (Re
       solveReferences;_CopyWebApplication target) (24:2) ->
       (_CopyWebApplicationLegacy target) ->
         C:\Program Files\MSBuild\Microsoft\VisualStudio\v10.0\WebApplications\
       Microsoft.WebApplication.targets(131,5): error MSB3021: Unable to copy f
       ile "obj\Debug\Nop.Web.dll" to "C:\Users\admin\Desktop\nop20\build\..\
       Deployable\nop_2.1\\bin\Nop.Web.dll". Could not find file 'obj\Debug\Nop
       .Web.dll'. [C:\Users\admin\Desktop\nop20\Presentation\Nop.Web\Nop.Web.
       csproj]

    0 Warning(s)
   1 Error(s)

Time Elapsed 00:00:08.70
Press any key to continue . . .



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please check the error and kindly send reply as soon as possible.

There was an issue in deploy.bat file in 2.10 version. Try 2.20 (released today)