With this you will surely solve the problem:
Accessing the Registry in Real Mode
Registry Editor runs in MS-DOS real mode. If you can boot your computer to MS-DOS mode, you can access Registry Editor. The file Regedit.exe is on the Windows startup disk and in the \Windows folder. For more information about using Regedit, type Regedit with no command line option at the command prompt, and a help screen appears advising you how to use this tool.
C:\WINDOWS\regedit
Imports and exports registry files to and from the registry.
REGEDIT [/L:system] [/R:user] filename1
REGEDIT [/L:system] [/R:user] /C filename2
REGEDIT [/L:system] [/R:user] /E filename3 [regpath]
REGEDIT [/L:system] [/R:user] /D regpath2
/L:system Specifies the location of the SYSTEM.DAT file.
/R:user Specifies the location of the USER.DAT file
Filename1 Specifies the file(s) to import into the registry
/C filename2 Specifies the file to create the registry from.
/E filename3 Specifies the file to export the registry to.
Regpath1 Specifies the starting registry key to export from.(Defaults to exporting the entire registry)
/D regpath2 Specifies the registry key to delete
To import a registry file into the registry in MS-DOS Registry Editor
On the Start menu, click Shut Down.
Select Restart in MS-DOS mode, and click OK.
At the MS-DOS command prompt, type:
REGEDIT /L:system /R:user filename
For example, the following command will import the contents of Global.reg into User.dat and System.dat:
REGEDIT /L:C:\Windows\/R:C:\Windows\Profiles\A:\Global.reg
