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This article describes the command-line switches you can use when you run the MS-DOS version (Scanreg.exe) or the Windows version (Scanregw.exe) of the Registry Checker tool.

More Information


MS-DOS Version:

Scanreg.exe [/backup] [/restore] ["/comment=<text>"] [/fix]
Scanreg.exe [backup] [/restore] ["/comment=<text>"] [/fix] [/opt]

Windows Version:

Scanregw.exe [/backup] ["/comment=<text>"] [/autoscan] [/scanonly] [filename]

Description of Switches

The following table lists each command-line switch and its description:

Switch Description
/backup Backs up the registry and related files without
displaying any prompts.

/restore Displays a list of available backup files, sorted
by the date and time the backup was created.

"/comment=<text>" Enables you to add a descriptive comment to the
registry backup.

/fix Repairs any damaged portions of the registry, and
optimizes it by rebuilding it without unused space.

/autoscan Automatically scans the registry and backs it up
without displaying any prompts if there is no
backup for that date.

/scanonly Scans the registry and displays a message if any
errors are found. This switch does not back up the

filename Scans the registry file specified and displays a
message indicating whether or not any errors were
found. This switch does not back up the registry.

/opt The /opt command-line switch causes the
Registry Checker tool to optimize the
registry by removing unused space.

The Registry Scan Results dialog box appears only when you use the Scanregw.exe command without any command-line switches. If no registry errors are found when you run Scanregw.exe, you are prompted to create a backup copy of your current registry.

The "/comment=<text>" switch can be used by itself or with the /backup switch. For example, you can type either of the following lines at a command prompt:

scanreg.exe "/comment=this is a registry backup"

scanreg.exe /backup "/comment=this is a registry backup"

The first command line starts the Registry Checker tool graphical user interface (GUI) and prompts you to create a registry backup. The second command line creates a backup copy of your registry and adds your comment without starting the Registry Checker tool GUI.

For additional information about the Registry Checker tool, please see the following articles in the Microsoft Knowledge Base:

183887 Description of the Windows Registry Checker Tool (Scanreg.exe)

183603 How to Customize Registry Checker Tool Settings

201655 Error Message: You Have Restored a Good Registry
For additional information about how to use the Registry Checker tool, click Start, click Help, click the Index tab, type registry, and then double-click the "Registry Checker" topic.

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