I have this problem, too.I've used the assembly binding log viewer (can be found at C:\Program Files\Microsoft SDKs\Windows\v6.0A\bin) to analyze what happens when the ValidateAddInXMLTask gets called. The log showed up like this:*** Assembly Binder Log Entry (13.4.2012 @ 9:21:45) ***
The operation failed.
Bind result: hr = 0x80070002. The system cannot find the file specified.
Assembly manager loaded from: C:\Windows\Microsoft.NET\Framework64\v4.0.30319\clr.dll
Running under executable C:\Windows\Microsoft.NET\Framework64\v4.0.30319\MSBuild.exe
--- A detailed error log follows.
=== Pre-bind state information ===
LOG: User = xxxxx
LOG: DisplayName = Microsoft.VisualStudio.Shell.9.0, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a
(Fully-specified)
LOG: Appbase = file:///C:/Windows/Microsoft.NET/Framework64/v4.0.30319/
LOG: Initial PrivatePath = NULL
LOG: Dynamic Base = NULL
LOG: Cache Base = NULL
LOG: AppName = MSBuild.exe
Calling assembly : ESRI.ArcGIS.AddIns.SDK, Version=10.0.0.0, Culture=neutral, PublicKeyToken=8fc3cc631e44ad86.
===
LOG: This bind starts in default load context.
LOG: Using application configuration file: C:\Windows\Microsoft.NET\Framework64\v4.0.30319\MSBuild.exe.Config
LOG: Using host configuration file:
LOG: Using machine configuration file from C:\Windows\Microsoft.NET\Framework64\v4.0.30319\config\machine.config.
LOG: Post-policy reference: Microsoft.VisualStudio.Shell.9.0, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a
LOG: GAC Lookup was unsuccessful.
LOG: Attempting download of new URL file:///C:/Windows/Microsoft.NET/Framework64/v4.0.30319/Microsoft.VisualStudio.Shell.9.0.DLL.
LOG: Attempting download of new URL file:///C:/Windows/Microsoft.NET/Framework64/v4.0.30319/Microsoft.VisualStudio.Shell.9.0/Microsoft.VisualStudio.Shell.9.0.DLL.
LOG: Attempting download of new URL file:///C:/Windows/Microsoft.NET/Framework64/v4.0.30319/Microsoft.VisualStudio.Shell.9.0.EXE.
LOG: Attempting download of new URL file:///C:/Windows/Microsoft.NET/Framework64/v4.0.30319/Microsoft.VisualStudio.Shell.9.0/Microsoft.VisualStudio.Shell.9.0.EXE.
LOG: All probing URLs attempted and failed.
I also found that the missing file Microsoft.VisualStudio.Shell.9.0.DLL is part of the Visual Studio SDK. So I downloaded the VS2010 SDK and installed it. Then I had to manually copy the file to the folder C:/Windows/Microsoft.NET/Framework64/v4.0.30319/ (the dll didn't register to the GAC).Now I'm stuck with error:C:\Program Files (x86)\MSBuild\ESRI\ESRI.ArcGIS.AddIns.targets (109): Missing required ArcGIS component(s). Make sure you have a valid ArcGIS runtime install.
with the log entry:*** Assembly Binder Log Entry (13.4.2012 @ 10:42:38) ***
The operation failed.
Bind result: hr = 0x80070002. The system cannot find the file specified.
Assembly manager loaded from: C:\Windows\Microsoft.NET\Framework64\v4.0.30319\clr.dll
Running under executable C:\Windows\Microsoft.NET\Framework64\v4.0.30319\MSBuild.exe
--- A detailed error log follows.
=== Pre-bind state information ===
LOG: User = xxxxxx
LOG: DisplayName = ESRI.ArcGIS.AddIns.SDK.resources, Version=10.0.0.0, Culture=en-US, PublicKeyToken=8fc3cc631e44ad86
(Fully-specified)
LOG: Appbase = file:///C:/Windows/Microsoft.NET/Framework64/v4.0.30319/
LOG: Initial PrivatePath = NULL
LOG: Dynamic Base = NULL
LOG: Cache Base = NULL
LOG: AppName = MSBuild.exe
Calling assembly : ESRI.ArcGIS.AddIns.SDK, Version=10.0.0.0, Culture=neutral, PublicKeyToken=8fc3cc631e44ad86.
===
LOG: This bind starts in default load context.
LOG: Using application configuration file: C:\Windows\Microsoft.NET\Framework64\v4.0.30319\MSBuild.exe.Config
LOG: Using host configuration file:
LOG: Using machine configuration file from C:\Windows\Microsoft.NET\Framework64\v4.0.30319\config\machine.config.
LOG: Post-policy reference: ESRI.ArcGIS.AddIns.SDK.resources, Version=10.0.0.0, Culture=en-US, PublicKeyToken=8fc3cc631e44ad86
LOG: GAC Lookup was unsuccessful.
LOG: Attempting download of new URL file:///C:/Windows/Microsoft.NET/Framework64/v4.0.30319/en-US/ESRI.ArcGIS.AddIns.SDK.resources.DLL.
LOG: Attempting download of new URL file:///C:/Windows/Microsoft.NET/Framework64/v4.0.30319/en-US/ESRI.ArcGIS.AddIns.SDK.resources/ESRI.ArcGIS.AddIns.SDK.resources.DLL.
LOG: Attempting download of new URL file:///C:/Windows/Microsoft.NET/Framework64/v4.0.30319/en-US/ESRI.ArcGIS.AddIns.SDK.resources.EXE.
LOG: Attempting download of new URL file:///C:/Windows/Microsoft.NET/Framework64/v4.0.30319/en-US/ESRI.ArcGIS.AddIns.SDK.resources/ESRI.ArcGIS.AddIns.SDK.resources.EXE.
LOG: All probing URLs attempted and failed.
I have no idea where to get the ESRI.ArcGIS.AddIns.SDK.resources.DLL from!