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By Mark Russinovich

• Well surprise, surprise, the July 2021 update to Windows Defender will attempt to delete any copies in multiple instances.txt file of source code - deleted.zip file with compiled.exe inside - deleted. Raw.exe file - deleted. Setting a Windows Defender exception to the folder does not prevent the quarantine from occurring. I re-ran this test.
• Select Start Settings System Display Night light settings. If your night light toggle above the link is grayed out, you may need to update your display driver. See Update drivers in Windows 10. Under Schedule, toggle Schedule night light to On. Then, either select Sunset to sunrise, or select Set hours and enter custom times for the.
• A simple utility exists that enables you to quickly change the SID and the computer name of a cloned virtual machine. The utility is called NewSID v4.10 and is available for download free of charge. NewSID is a program we developed to change a computer's SID.

According to Microsoft, Windows 10 1809 can use more than 300 of these, one of the most commonly encountered of which looks like this: S-1-15-3-10974687. In Windows 10, Sysprep also includes a VM mode, which generalizes a VHD that you deploy as a VHD on the same virtual machine or hypervisor. This mode supports rapid deployment of virtual machines.

Published: November 1, 2006

Note: NewSID has been retired and is no longer available fordownload. Please see Mark Russinovich’s blog post: NewSID Retirementand the Machine SID DuplicationMyth

IMPORTANT

Regarding SIDs, Microsoft does not support images that are preparedusing NewSID, we only support images that are prepared using SysPrep.Microsoft has not tested NewSID for all deployment cloning options.

For more information on Microsoft's official policy, please see thefollowing Knowledge Base article:

Introduction

Many organizations use disk image cloning to perform mass rollouts ofWindows. This technique involves copying the disks of a fully installedand configured Windows computer onto the disk drives of other computers.These other computers effectively appear to have been through the sameinstall process, and are immediately available for use.

While this method saves hours of work and hassle over other rolloutapproaches, it has the major problem that every cloned system has anidentical Computer Security Identifier (SID). This fact compromisessecurity in Workgroup environments, and removable media security canalso be compromised in networks with multiple identical computer SIDs.

Demand from the Windows community has lead several companies to developprograms that can change a computer's SID after a system has beencloned. However, Symantec's SID Changer andSymantec's Ghost Walker areonly sold as part of each company's high-end product. Further, they bothrun from a DOS command prompt (Altiris' changer is similar toNewSID).

NewSID is a program we developed that changes a computer's SID. It isfree and is a Win32 program, meaning that it can easily be run onsystems that have been previously cloned.

Please read this entire article before you use this program.

Version Information:

• Version 4.0 introduces support for Windows XP and .NET Server, awizard-style interface, allows you to specify the SID that you wantapplied, Registry compaction and also the option to rename acomputer (which results in a change of both NetBIOS and DNS names).
• Version 3.02 corrects a bug where NewSid would not correctly copydefault values with invalid value types when renaming a key with anold SID to a new SID. NT actually makes use of such invalid valuesat certain times in the SAM. The symptom of this bug was errormessages reporting access denied when account information wasupdated by an authorized user.
• Version 3.01 adds a work-around for an inaccessible Registry keythat is created by Microsoft Transaction Server. Without thework-around NewSID would quit prematurely.
• Version 3.0 introduces a SID-sync feature that directs NewSID toobtain a SID to apply from another computer.
• Version 2.0 has an automated-mode option, and let's you change thecomputer name as well.
• Version 1.2 fixes a bug in that was introduced in 1.1 where somefile system security descriptors were not updated.
• Version 1.1 corrects a relatively minor bug that affected onlycertain installations. It also has been updated to change SIDsassociated with the permission settings of file and printer shares.

Cloning and Alternate Rollout Methods

One of the most popular ways of performing mass Windows rollouts(typically hundreds of computers) in corporate environments is based onthe technique of disk cloning. A system administrator installs the baseoperating system and add-on software used in the company on a templatecomputer. After configuring the machine for operation in the companynetwork, automated disk or system duplication tools (such asSymantec'sGhost,PowerQuest'sImage Drive, andAltiris'RapiDeploy) are used to copy thetemplate computer's drives onto tens or hundreds of computers. Theseclones are then given final tweaks, such as the assignment of uniquenames, and then used by company employees.

Another popular way of rolling out is by using the Microsoft sysdiffutility (part of the Windows Resource Kit). This tool requires that thesystem administrator perform a full install (usually a scriptedunattended installation) on each computer, and then sysdiff automatesthe application of add-on software install images.

Because the installation is skipped, and because disk sector copying ismore efficient than file copying, a cloned-based rollout can save dozensof hours over a comparable sysdiff install. In addition, the systemadministrator does not have to learn how to use unattended install orsysdiff, or create and debug install scripts. This alone saves hoursof work.

The SID Duplication Problem

The problem with cloning is that it is only supported by Microsoft in avery limited sense. Microsoft has stated that cloning systems is onlysupported if it is done before the GUI portion of Windows Setup has beenreached. When the install reaches this point the computer is assigned aname and a unique computer SID. If a system is cloned after this stepthe cloned machines will all have identical computer SIDs. Note thatjust changing the computer name or adding the computer to a differentdomain does not change the computer SID. Changing the name or domainonly changes the domain SID if the computer was previously associatedwith a domain.

To understand the problem that cloning can cause, it is first necessaryto understand how individual local accounts on a computer are assignedSIDs. The SIDs of local accounts consist of the computer's SID and anappended RID (Relative Identifier). The RID starts at a fixed value, andis increased by one for each account created. This means that the secondaccount on one computer, for example, will be given the same RID as thesecond account on a clone. The result is that both accounts have thesame SID.

Duplicate SIDs aren't an issue in a Domain-based environment sincedomain accounts have SID's based on the Domain SID. But, according toMicrosoft Knowledge Base article Q162001, 'Do Not Disk DuplicateInstalled Versions of Windows NT', in a Workgroup environment securityis based on local account SIDs. Thus, if two computers have users withthe same SID, the Workgroup will not be able to distinguish between theusers. All resources, including files and Registry keys, that one userhas access to, the other will as well.

Another instance where duplicate SIDs can cause problems is where thereis removable media formatted with NTFS, and local account securityattributes are applied to files and directories. If such a media ismoved to a different computer that has the same SID, then local accountsthat otherwise would not be able to access the files might be able to iftheir account IDs happened to match those in the security attributes.This is not be possible if computers have different SIDs.

An article Mark has written, entitled 'NT Rollout Options,' waspublished in the June issue of Windows NT Magazine. It discusses theduplicate SID issue in more detail, and presents Microsoft's officialstance on cloning. To see if you have a duplicate SID issue on yournetwork, usePsGetSidto display machine SIDs.

NewSID

NewSID is a program we developed to change a computer's SID. It firstgenerates a random SID for the computer, and proceeds to updateinstances of the existing computer SID it finds in the Registry and infile security descriptors, replacing occurrences with the new SID.NewSID requires administrative privileges to run. It has twofunctions: changing the SID, and changing the computer name.

To use NewSID's auto-run option, specify '/a' on the command line. Youcan also direct it to automatically change the computer's name byincluding the new name after the '/a' switch. For example:

newsid /a [newname]

Would have NewSID run without prompting, change the computer name to'newname' and have it reboot the computer if everything goes okay.

Note: If the system on which you wish to run NewSID is runningIISAdmin you must stop the IISAdmin service before running NewSID. Usethis command to stop the IISAdmin service: net stop iisadmin /y

NewSID's SID-synchronizing feature that allows you to specify that,instead of randomly generating one, the new SID should be obtained froma different computer. This functionality makes it possible to move aBackup Domain Controller (BDC) to a new Domain, since a BDC'srelationship to a Domain is identified by it having the same computerSID as the other Domain Controllers (DCs). Simply choose the'Synchronize SID' button and enter the target computer's name. You musthave permissions to change the security settings of the targetcomputer's Registry keys, which typically means that you must be loggedin as a domain administrator to use this feature.

Note that when you run NewSID that the size of the Registry will grow,so make sure that the maximum Registry size will accommodate growth. Wehave found that this growth has no perceptible impact on systemperformance. The reason the Registry grows is that it becomes fragmentedas temporary security settings are applied by NewSID. When thesettings are removed the Registry is not compacted.

Important: Note that while we have thoroughly tested NewSID, youmust use it at your own risk. As with any software that changes file andRegistry settings, it is highly recommended that you completely back-upyour computer before running NewSID.

Moving a BDC

Here are the steps you should follow when you want to move a BDC fromone domain to another:

1. Boot up the BDC you want to move and log in. Use NewSID tosynchronize the SID of the BDC with the PDC of the domain to whichyou wish to move the BDC.
2. Reboot the system for which you changed the SID (the BDC). Since thedomain the BDC is now associated with already has an active PDC, itwill boot as a BDC in its new domain.
3. The BDC will show up as a workstation in Server Manager, so use the'Add to Domain' button to add the BDC to its new domain. Be sure tospecify the BDC radio button when adding.

How it Works

NewSID starts by reading the existing computer SID. A computer's SIDis stored in the Registry's SECURITY hive underSECURITYSAMDomainsAccount. This key has a value named F and avalue named V. The V value is a binary value that has the computer SIDembedded within it at the end of its data. NewSID ensures that thisSID is in a standard format (3 32-bit subauthorities preceded by three32-bit authority fields).

Next, NewSID generates a new random SID for the computer. NewSID'sgeneration takes great pains to create a truly random 96-bit value,which replaces the 96-bits of the 3 subauthority values that make up acomputer SID.

Three phases to the computer SID replacement follow. In the first phase,the SECURITY and SAM Registry hives are scanned for occurrencesof the old computer SID in key values, as well as the names of the keys.When the SID is found in a value it is replaced with the new computerSID, and when the SID is found in a name, the key and its subkeys arecopied to a new subkey that has the same name except with the new SIDreplacing the old.

The final two phases involve updating security descriptors. Registrykeys and NTFS files have security associated with them. Securitydescriptors consist of an entry that identifies which account owns theresource, which group is the primary group owner, an optional list ofentries that specify actions permitted by users or groups (known as theDiscretionary Access Control List - DACL), and an optional list ofentries that specify which actions performed by certain users or groupswill generate entries in the system Event Log (System Access ControlList - SACL). A user or a group is identified in these securitydescriptors with their SIDs, and as I stated earlier, local useraccounts (other than the built-in accounts such as Administrator, Guest,and so on) have their SIDs made up of the computer SID plus a RID.

The first part of security descriptor updates occurs on all NTFS filesystem files on the computer. Every security descriptor is scanned foroccurrences of the computer SID. When NewSID finds one, it replaces itwith the new computer SID.

The second part of security descriptor updates is performed on theRegistry. First, NewSID must make sure that it scans all hives, notjust those that are loaded. Every user account has a Registry hive thatis loaded as HKEY_CURRENT_USER when the user is logged in, butremains on disk in the user's profile directory when they are not.NewSID identifies the locations of all user hive locations byenumerating the HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsNTCurrentVersionProfileList key, which points at the directoriesin which they are stored. It then loads them into the Registry usingRegLoadKey under HKEY_LOCAL_MACHINE and scans the entire Registry,examining each security descriptor in search of the old computer SID.Updates are performed the same as for files, and when its done NewSIDunloads the user hives it loaded. As a final step NewSID scans theHKEY_USERS key, which contains the hive of the currently logged-inuser as well as the .Default hive. This is necessary because a hivecan't be loaded twice, so the logged-in user hive won't be loaded intoHKEY_LOCAL_MACHINE when NewSID is loading other user hives.

Sid Changer For Windows 10

Finally, NewSID must update the ProfileList subkeys to refer tothe new account SIDs. This step is necessary to have Windows NTcorrectly associate profiles with the user accounts after the accountSIDs are changed to reflect the new computer SID.

NewSID ensures that it can access and modify every file and Registrykey in the system by giving itself the following privileges: System,Backup, Restore and Take Ownership.

What is the Security Identifier (SID)?

A security identifier (SID) is a unique value of variable length used to identify a trustee. Each account has a unique SID issued by an authority, such as a Windows domain controller, and stored in a security database. Each time a user logs on, the system retrieves the SID for that user from the database and places it in the access token for that user. The system uses the SID in the access token to identify the user in all subsequent interactions with Windows security. When a SID has been used as the unique identifier for a user or group, it cannot ever be used again to identify another user or group.

How to change the SID?

In a WORKGROUP of computers running Windows, it is possible for a user to have unexpected access to shared files or files stored on removable storage. This can be prevented by setting access control lists on a susceptible file, such that the effective permissions are determined by the user SID. If this user SID is duplicated on another computer, a user of a secondcomputer having the sameSID could have access to the files that the user of a firstcomputer has protected. This can often happen when machine SIDs are duplicated by a disk clone, common for pirate copies. The user SIDs are built based on the machine SID and a sequential relative ID.

In order to duplicate SIDs prevention, the only supported Windows operating systems are through use of SysPrep the built-in Windows tool, which generates new SIDs. The following are the short steps on how to change the SIDs safely.

Sid Changer Windows 10 64-bit

Check the current SID by running the following command in Powershell. In order to compare the change.

Sid Changer Utility Windows 10

>whoami /all

Open Windows Explorer > Go to C:WindowsSystem32Sysprep, run the sysprep.exe

Tick the checkbox Generalize, then click OK to proceed with the change.

Sysprep is working, It will require a machine restart to re-settings.

Acronis Sid Changer Windows 10

Restart your machine, re-settings as Windows recommend.

Once done, try to run the command whoami /all for double-check after the change. The SID will be changed to another one.

That’s it. Now your machine has a unique SID. Hope it helps.

Sid Changer Windows 10 Free