Windows OS and file named hosts.

This link tell us about hosts and how to fix into default mode.
But also you can block or not some unwanted connections.

Example:
The 0.0.0.0 (prefix) is considered the location of your computer, so when an entry listed in the MVPS HOSTS file is requested on a page you are viewing, your computer thinks 0.0.0.0 is the location of the file.

Also some got some infos from regedit tool.

Error: No Internet access from IPv6 .

If you see the IPv6 No network access from Ethernet Status dialog then you can try this tutorial.
Use Start menu then type cmd to start the Command Prompt shell and use right click choose Run as administrator.
Use this commands into shell:

You can also use the ipconfig command-line tool

Opera browser – multiple profiles .

The Opera browser let you to use multiple profiles.
This feature allow you to have a new clean profile by select a folder profile.
To use this feature you need to start from folder where the Opera browser is install with this command.

This will start the Opera browser the same way as in the first installation.

Windows 10 – SubInACL tool.

This tool can be found at microsoft website and is a powerful tool.
After install the tool complete html documentation with useful examples.
You must run this command with administrator privileges.
Also they tell us about this tool:
SubInACL is a command-line tool that enables administrators to obtain security information about files, registry keys, and services, and transfer this information from user to user, from local or global group to group, and from domain to domain.

For example, if a user has moved from one domain (DomainA) to another (DomainB), the administrator can replace DomainA\User with DomainB\User in the security information for the user’s files. This gives the user access to the same files from the new domain.

SubInACL enables administrators to do the following:

Display security information associated with files, registry keys, or services. This information includes owner, group, permission access control list (ACL), discretionary ACL (DACL), and system ACL (SACL).
Change the owner of an object.
Replace the security information for one identifier (account, group, well-known security identifier (SID)) with that of another identifier.
Migrate security information about objects. This is useful if you have reorganized a network’s domains and need to migrate the security information for files from one domain to another.

For example:

come with infos like :