Error "Registry Editing has been disabled by your administrator"

Copy complete commend and Paste in run window and press enter which you want to enable
Task manager:
REG add HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System /v DisableTaskMgr /t REG_DWORD /d 0 /f


Regedit:
REG add HKCU\Software\Microsoft\Windows\CurrentVersion\Pol icies\System /v DisableRegistryTools /t REG_DWORD /f /d 0


reg add "HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System" /t Reg_dword /v DisableRegistryTools /f /d 0



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make a .reg file and save : then run it

Windows Registry Editor Version 5.00
 
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\System]
"DisableTaskMgr"=dword:00000000
 
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Group Policy Objects\LocalUser\Software\Microsoft\Windows\CurrentVersion\Policies\System]
"DisableTaskMgr"=dword:00000000

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\system\]
"DisableTaskMgr"=dword:00000000
 
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon]
"DisableCAD"=dword:00000000

System Restore has been turned off by group policy

Solution : Click Here

1. Click Start, Run and type regedit.exe and press Enter
2. Navigate to the following key:
HKEY_LOCAL_MACHINE \ Software \ Policies \ Microsoft \ Windows NT \ SystemRestore
In the right-pane:
Delete the value DisableConfig
Delete the value DisableSR
3. Exit the Registry Editor.

In Windows XP Professional, you can accomplish the above using Group Policy Editor as well.

1. Click Start, Run and type GPEDIT.MSC
2. Navigate to this path:
-> Computer Configuration--> Administrative Templates---> System----> System Restore
3. Set Turn off System Restore to Not Configured
4. Set Turn off Configuration to Not Configured
More Information
Turn off System Restore corresponds to DisableSR registry value. With this Policy is turned ON, the System Restore tab may be missing in My Computer Properties. Also, when you run System Restore (rstrui.exe), you receive this message:
System Restore has been turned off by group policy. To turn on System Restore, contact your domain Administrator.
Turn off Configuration corresponds to DisableConfig registry value. With this Policy turned ON, the System Restore tab will remain displayed but the user cannot configure the SR options. It reads disabled by Group Policy