Regedit Command Line Switches
Although not mentioned in the documentation, the Windows Registry Editor has a number of options for manipulating the Windows registry from the command line. Here are the syntax and usage examples.
Registry Exporting
To export all registry contens to the c:\all.reg file, use the /e switch as follows:
regedit /E c:\all.reg
To export a specific registry key to the file.reg file, use the /e switch as follows:
regedit /E file.reg <registry_key>
For example, the following command exports the list of startup programs from the "HKLM\Run" key:
regedit /E c:\hklm_run.reg "HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run"
Registry Importing
Merge or import file.reg into a registry:
regedit file.reg
Registry Deleting
Deleting a Registry Key
To delete a specific registry key from the registry, you can create the .reg file and specify the minus sign before the key name to delete, here is the example file contents of c:\del.reg:
Windows Registry Editor Version 5.00
[-HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\System]
Now launch the Regedit using regedit c:\del.reg
and the key HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\System will be removed from the system registry.
In the earlier Windows versions, Regedit has the /D switch, use it as follows:
regedit /D <registry_key>
For example, the following command will delete the entry of the CWS trojan:
regedit /D "HKEY_CLASSES_ROOT\CLSID\{834261E1-DD97-4177-853B-C907E5D5BD6E}"
Deleting a Registry Value
To delete a specific registry value, specify the minus sign instead of a value in the .reg file:
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer]
"CleanShutdown"=-
Other Switches
For silent execution of the Regedit program, use the /s parameter. If /s is specified, Regedit will suppress any informational dialog boxes and operate quietly, without asking for confirmation.
There are also command line switches for specifying location of User.dat (/L) and user name (/R):
regedit /L:c:\windows\user.dat /e c:\test.reg