Managing Extensions and Updates for Visual Studio
You can use the Extensions and Updates dialog box to install Visual Studio extensions and samples from websites and other locations, and then enable, disable, update, or uninstall them. To open the dialog box, on the menu bar, choose Tools, Extensions and Updates. (Or in the Quick Launch box, just type Extensions.)
You can install extensions from the Visual Studio Gallery or the Sample Gallery on the Microsoft website. Extensions may be controls, samples, templates, tools, or other components that add functionality to Visual Studio. Visual Studio supports extensions in the VSIX package format—these include project templates, item templates, Toolbox items, Managed Extension Framework (MEF) components, and VSPackages. Microsoft Installer (MSI)-based extensions are also supported for download and installation, but the Extensions and Updates dialog box can't enable or disable them.
Installing or Uninstalling Extensions
In the Extensions and Updates dialog box, in the left pane, expand Online and select Visual Studio Gallery. If you know the name of the extension or part of its name, you can search in the Search Visual Studio Gallery box in the right pane, or you can browse through the list in the middle pane. Select the extension you want, choose the Download button, and then choose Install. To load the extension, you must restart Visual Studio.
If you try to install an extension that has dependencies, the installer verifies whether they're already installed. If they aren't installed, the Extensions and Updates dialog box lists the dependencies that must be installed before you can install the extension.
If you want to stop using an extension, you can either disable it or uninstall it. Disabling an extension keeps it installed but unloaded. You can disable only VSIX extensions; MSI extensions can only be uninstalled. To disable or uninstall an extension, in the left pane, select Installed, in the middle pane, select the extension, and then choose either the Disable button or the Uninstall button. To unload a disabled extension, you must restart Visual Studio.
You can uninstall only those extensions that were installed on a per-user basis. You can't uninstall extensions that were installed on a per-machine basis—for example, NuGet.
Per-User and Administrative Extensions
Most extensions are per-user extensions, which are installed in %LocalAppData%\Microsoft\VisualStudio\<Visual Studio version>\Extensions\. Some extensions are administrative extensions, which are installed in <Visual Studio installation folder>\Common7\IDE\Extensions\.
To protect your system against extensions that may contain errors or malicious code, you can restrict per-user extensions to load only when Visual Studio is run with normal user permissions and not load when Visual Studio is run with administrative user permissions. To do this, on the menu bar, choose Tools, Options, and then in the Options dialog box, expand Environment and select Extensions and Updates. (You can also just type Extension in the Quick Launch box.) Clear the Load per user extensions when running as administrator check box and then restart Visual Studio.
Master Copies and Working Copies
When you install an online sample, the solution is stored in two locations:
A working copy is stored in the location that you specified in the New Project dialog box.
A separate master copy is stored on your computer.
You can use the Extensions and Updates dialog box to perform these samples-related tasks:
List the master copies of samples that you have installed.
Disable or uninstall the master copy of a sample.
Install Sample Packs, which are collections of samples that relate to a technology or feature.
Install individual online samples. (You can also do this in the New Project dialog box.)
View update notifications when source code changes are published for installed samples.
Update the master copy of an installed sample when there an update is available.
Installing Without Using the Extensions and Updates Dialog Box
Extensions that have been packaged in .vsix files may be available in locations other than the Visual Studio Gallery. Although the Extensions and Updates dialog box can't detect these files, you can install one by selecting its .vsix file, pressing the Enter key, and then following the instructions. When the extension is installed, you can use the Extensions and Updates dialog box to enable it, disable it, or uninstall it.
The Extensions and Updates dialog box doesn't support MSI-based extensions unless they include an extension.vsixmanifest file. Such extensions appear in the Extensions and Updates for installation or uninstallation, but they cannot be enabled, disabled, or updated