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Q: An error occurred... Microsoft Exchange WebServices... when developing SharePoint 2013 in VS 2013 I have a development environment setup with these components


*

*SharePoint 2013

*Windows 2012 R2

*Visual Studio 2013


SharePoint is up and running just fine.
I am however getting an error when trying to add SharePoint items to my solution in the Visual Studio project.

An error occurred while trying to load a required component. Please
  ensure that the following prerequisite component is installed:
  Microsoft Exchange WebServices


I have tried the well known EwsManagedApi32.msi addlocal=ExchangeWebServicesApi_Feature,ExchangeWebServicesApi_Gac from an elevated command prompt. This error rather seems to be that VS 2013 dont recognize the EWS assemblies.
Any advices are welcome, thanks

A: This can happen if you install just the developer tools without the complete set of prerequisites. You could try fixing your setup by closing Visual Studio and then following steps:
1.Go to Control Panel > Uninstall a program
2.Select Microsoft Office Developer Tools for Visual Studio 2012
3.Click on Change to uninstall it. The setup program should launch.
4.Click on Uninstall to remove the Office Developer Tools.
5.Download the Office Developer Tools using this Web Platform Installer link from the Get It Now section of the blog announcing the latest release of Office Developer Tools. This Web Platform Installer should install the Office Developer Tools and all the prerequisites (Exchange Web Services, LightSwitch HTML Client, etc).
6.Try creating your SharePoint 2013 Empty Project again.
Link

A: Uninstalling and Reinstalling Visual Studio 2013 solved this issue.

A: I uninstalled and re-installed Microsoft Exchange Web Services Managed API 2.0 with 64 bit version that helped fixing the issue.
This reference give you step by step installation Link
Microsoft Link to download 

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The text includes 129 "t"s in total.
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