- How to Create Symbolic Links (Symlink) in Windows 10
- What Are Symbolic Links?
- Create Symbolic Link Using Link Shell Extension
- Create Symbolic Link Using Mklink
- Create symbolic links
- Reference
- Possible values
- Best practices
- Location
- Default values
- Policy management
- Group Policy
- Command-line tools
- Security considerations
- Vulnerability
- Countermeasure
- Potential impact
- Symlinks in Windows 10!
- Overview
- Background
- What drove this change?
- How to use Symlinks
- How do I try it?
How to Create Symbolic Links (Symlink) in Windows 10
Symlinks or Symbolic Links is one of the lesser known, yet useful, features in Windows. You can think of symbolic links as the shortcuts you create in Windows. However, symbolic links are much more powerful and helpful than regular shortcuts. Let’s discuss what symbolic links are and how you can easily create them in Windows 10.
What Are Symbolic Links?
When you create a shortcut for a file or folder, all you are doing is pointing it to that specific file or folder, nothing more. Symbolic links are much more than a simple shortcut. They act as a virtual file or folder that links to the actual file or folder.
When you create a symlink for a file, it appears as if it is the actual file when in reality it is redirecting you toward the real file in the background. Besides files, you can also create symlinks for folders. Simply put, a symlink is nothing more than a build of the text string which lets the operating system know that it is just a path for another file or folder.
For instance, most cloud service apps you install will only sync files and folders located in their own folder. But there will be times when you might have a folder in some other drive you want to sync with the cloud storage service.
However, you don’t want to move the folder from its actual location or don’t want to create a copy of the folder. In those situations you can simply create a symlink in the cloud service folder so that you can sync the contents of the target folder without actually moving or copying the real folder.
Since a symlink is just a virtual folder that just acts as a path to the real folder, you don’t have to worry about the symlink consuming your disk space.
Create Symbolic Link Using Link Shell Extension
If you don’t want to faff around in the Command Prompt and are prepared to faff around a little bit by installing a tool that lets you create symlinks to an existing file or directory using the right-click context menu, then try the following. Link Shell Extension is a tool that lets you create hardlinks and symbolic links by right-clicking whatever folder you want to create a link to.
There are a few hoops with the installation. You’ll get a warning that it can’t be downloaded securely, and Windows Defender may warn you that it’s “unsigned.”
We can assure you that the tool is safe. Go ahead and install it. During installation, explorer.exe will restart, so make sure you have important stuff backed up.
Once LSE is installed, right-click the target file or folder you want to create a symlink to, then click “Pick Link Source.”
Next, go to the folder where you want the symlink to appear, right-click it, then select “Drop As -> Symbolic Link.”
Create Symbolic Link Using Mklink
Note: though I’m showing this in Windows 10, the commands shown here are applicable to Windows Vista and up.
Creating symlinks in Windows is pretty easy with the mklink command. To start, press Win + X , then select the option “Command Prompt (Admin)” to open the Command Prompt with admin rights.
Once the command prompt has been opened, use the below command format to create a symlink for a file.
In my case, I want to create a symlink in the E drive for a text file located on the F drive, so the command looks something like this:
The first path you see in the above command is where you will create your symlink. This path is called a “Link.” The second path belongs to the actual file on your disk and is called “Target.”
Once the symlink has been created, this is how it looks in the File Explorer. Though the icon looks like a regular shortcut, it is a symlink.
Along with individual files, you can create symlinks for entire directories. To do that, use the below command. The switch /D allows you to do this.
As soon as you execute the command, the symlink will be created for the target directory. You can use it to access all the files and folders inside the real folder. If you ever want to, you can delete the symbolic link like any other file or folder. Just select the symlink, press the delete key on your keyboard, and you are good to go.
And you’re done! If you want to do more under-the-hood tweaking in Windows 10, see our list of the best registry hacks. Also, check out our guide on how to get Mac-style hot corners in Windows 10.
Create symbolic links
Applies to
Describes the best practices, location, values, policy management, and security considerations for the Create symbolic links security policy setting.
Reference
This user right determines if users can create a symbolic link from the device they are logged on to.
A symbolic link is a file-system object that points to another file-system object. The object that’s pointed to is called the target. Symbolic links are transparent to users. The links appear as normal files or directories, and they can be acted upon by the user or application in exactly the same manner. Symbolic links are designed to aid in migration and application compatibility with UNIX operating systems. Microsoft has implemented symbolic links to function just like UNIX links.
Warning:В В В This privilege should only be given to trusted users. Symbolic links can expose security vulnerabilities in applications that aren’t designed to handle them. Constant: SeCreateSymbolicLinkPrivilege
Possible values
- User-defined list of accounts
- Not Defined
Best practices
- Only trusted users should get this user right. Symbolic links can expose security vulnerabilities in applications that are not designed to handle them.
Location
Computer Configuration\Windows Settings\Security Settings\Local Policies\User Rights Assignment
Default values
By default, members of the Administrators group have this right.
The following table lists the actual and effective default policy values. Default values are also listed on the policy’s property page.
Server type or GPO | Default value |
---|---|
Default Domain Policy | Not Defined |
Default Domain Controller Policy | Not Defined |
Stand-Alone Server Default Settings | Not Defined |
Domain Controller Effective Default Settings | Administrators |
Member Server Effective Default Settings | Administrators |
Client Computer Effective Default Settings | Administrators |
Policy management
This section describes different features and tools available to help you manage this policy.
A restart of the device is not required for this policy setting to be effective.
Any change to the user rights assignment for an account becomes effective the next time the owner of the account logs on.
Group Policy
Settings are applied in the following order through a Group Policy Object (GPO), which will overwrite settings on the local computer at the next Group Policy update:
- Local policy settings
- Site policy settings
- Domain policy settings
- OU policy settings
When a local setting is greyed out, it indicates that a GPO currently controls that setting.
Command-line tools
This setting can be used in conjunction with a symbolic link file system setting that can be manipulated with the command-line tool to control the kinds of symlinks that are allowed on the device. For more info, type fsutil behavior set symlinkevaluation /? at the command prompt.
Security considerations
This section describes how an attacker might exploit a feature or its configuration, how to implement the countermeasure, and the possible negative consequences of countermeasure implementation.
Vulnerability
Users who have the Create symbolic links user right could inadvertently or maliciously expose your system to symbolic link attacks. Symbolic link attacks can be used to change the permissions on a file, to corrupt data, to destroy data, or as a DoS attack.
Countermeasure
Do not assign the Create symbolic links user right to standard users. Restrict this right to trusted administrators. You can use the fsutil command to establish a symbolic link file system setting that controls the kind of symbolic links that can be created on a computer.
Potential impact
None. Not defined is the default configuration.
Symlinks in Windows 10!
Overview
Symlinks, or symbolic links, are “virtual” files or folders which reference a physical file or folder located elsewhere, and are an important feature built in to many operating systems, including Linux and Windows.
The Windows’ NTFS file system has supported symlinks since Windows Vista. However, it hasn’t been easy for Windows developers to create symlinks. In our efforts to continually improve the Windows Developer experience we’re fixing this!
Starting with Windows 10 Insiders build 14972, symlinks can be created without needing to elevate the console as administrator. This will allow developers, tools and projects, that previously struggled to work effectively on Windows due to symlink issues, to behave just as efficiently and reliably as they do on Linux or OSX.
Background
A symlink is essentially a pointer to a file or folder located elsewhere, consumes little space and is very fast to create (compared to copying a file and its contents).
Because of this, developers often replace duplicate copies of shared files/folders with symlinks referencing physical files/folders. Replacing redundant copies of files can save a great deal of physical disk space, and significantly reduce the time taken to copy/backup/deploy/clone projects.
In UNIX-compatible operating systems like Linux, FreeBSD, OSX, etc., symlinks can be created without restrictions.
However, for Windows users, due to Windows Vista’s security requirements, users needed local admin rights and, importantly, had to run mklink in a command-line console elevated as administrator to create/modify symlinks. This latter restriction resulted in symlinks being infrequently used by most Windows developers, and caused many modern cross-platform development tools to work less efficiently and reliably on Windows.
Now in Windows 10 Creators Update, a user (with admin rights) can first enable Developer Mode, and then any user on the machine can run the mklink command without elevating a command-line console.
What drove this change?
The availability and use of symlinks is a big deal to modern developers:
Many popular development tools like git and package managers like npm recognize and persist symlinks when creating repos or packages, respectively. When those repos or packages are then restored elsewhere, the symlinks are also restored, ensuring disk space (and the user’s time) isn’t wasted.
Git, for example, along with sites like GitHub, has become the main go-to-source code management tool used by most developers today.
Figure 1: SCM Tool Trends 2004-2016 (Source, Google)
The use of package managers in modern development has also exploded in recent years. For example, node package manager (npm) served
400 million installs in the week of July 1 st 2015, but served more than 1.2 billion installs just one year later – a 3x increase in just one year! In late June 2016, npm served more than 1.7 billion node packages in just seven days!
Figure 2: npm served 1.2Bn downloads in the first week of July 2016
There are clear drivers demanding that Windows enables the ability to create symlinks to non-admin users:
- Modern development projects are increasingly portable across operating systems
- Modern development tools are symlink-aware, and many are optimized for symlinks
- Windows developers should enjoy a development environment that is at least the equal of others
How to use Symlinks
Symlinks are created either using the mklink command or the CreateSymbolicLink API
mklink
- There is no change in how to call mklink. For users who have Developer Mode enabled, the mklink command will now successfully create a symlink if the user is not running as an administrator.
CreateSymbolicLink
- To enable the new behavior when using the CreateSymbolicLink API, there is an additional dwFlags option you will need to set:
Value | Meaning |
SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE 0x2 | Specify this flag to allow creation of symbolic links when the process is not elevated |
Example Use
In the example below:
- A subfolder folder called “animals” containing three files (cat.txt, dog.txt, and fish.txt)
- (green) The mklink command is executed to create a symlink called “pet.txt” pointing at the “animalsdog.txt” file
- (blue) When the contents of the current folder are listed, the symlink can be seen (yellow)
- (purple) When contents of pet.txt are queried, the content of the referenced file (“dog.txt”) is displayed
Once created, symlinks can be opened, loaded, deleted, etc., just like any other file. Here, the pet.txt symlink is being opened in Notepad (red):
How do I try it?
This new symlinks support first shipped in Windows 10 Insiders Build 14972, and will be formally delivered in Windows 10 Creators Update. We are also working with the owners of open-source community tools such as Git and npm so they know symlink improvements are coming and can make the necessary changes to better support symlinks on Windows.
We encourage you to take this new feature for a spin and be sure to let us know via the Windows 10 Feedback hub or on Twitter etc. (see below). Please sign up for the Windows Insiders program if you haven’t already to try out symlinks!