How to disable windows task manager?

To disable task manager permanently you will need to follow these instructions carefully, REMEMBER; here you are in the REGISTRY and mistakes may cost the operating system to crush:: Go to this page and download a small GUI. This small GUI (Graphical User Interface) utility allows you to easily enable or disable Task Manager. The only time its useful, or effective, is when you see this error message when you try to use Task Manager. OR
Disable Task Manager Task Manager has setting controls that anable for users to start and Task programs and view processes, running applications and make changes to the priority or state of the individual processes. To disable it you will need to do the following :
Click "start" click "Run" type "regedit" enter this opens your registry then find the key below.
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\System]
Create a new DWORD valued named "DisableTaskMgr" and set it to= "1" to disable Task Manager. to re-enable it set it to= "0" Don't forget you may need to log off for the changes to take effect.

download Unhook.ini from norton site. Run it as administartor. It should get fixed.
Cheers!

Since you didn't said what kind of vista you have all i can do is show you this
http://www.vistax64.com/tutorials/103275-task-manager-enable-disable.html

Try this:

If Task Manager has been disabled, you can re-enable it if you have administrator privileges on the computer.
To enable Task Manager on a computer running Windows Vista Home Basic or Windows Vista Home Premium This procedure requires you to edit the registry. An incorrect change to your computer's registry could render your computer inoperable. We strongly recommend that you back up the registry before making any changes. For more information, see Back up the registry.

1. Open the Registry Editor by clicking the Start button , typing regedit into the Search box, and then pressing ENTER.‌ If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
   
2. Navigate to the following location: HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies
   
3. Double-click System, double-click DisableTaskMgr, change Value data to 0, and then click OK.
   

To enable task Manager on a computer running other editions of Windows Vista

1. Click the Start button , type gpedit.msc in the search box, and then press ENTER.
   
2. Under User Configuration, double-click Administrative Templates.
   
3. Double-click System, and then click Crtl+Alt+Del Options.
   
4. Double-click Remove Task Manager, click Disabled, and then click OK.
   

or you're computer might be infected by a virus, if you're not the one who disabled the task manager.

Try to scan your computer also.

So your task mananger isn't working, this may be a Virus, or simply some programs error? Anyway, If you have Windows XP Pro, there's a nifty user interface to directly edit the setting you want to repair. Click Start, then click Run and type in gpedit.msc: And press OK. This runs the Group Policy Editor. Once in the Group Policy Editor, expand in turn: User Configuration Administrative Templates System Ctrl+Alt+Del Options You should see the Group Policy Window, Double click on Remove Task Manager to change its setting: It should be enough to click on Not Configured and then OK and Task Manager is available once again. If you don't have Windows XP Pro, then you'll need to edit the registry manually. Click Start, then click Run, type in regedit, and click on OK. Expand these registry keys in turn:
HKEY_CURRENT_USER \Software \Microsoft \Windows \CurrentVersion \Policies \System You should see the key DisableTaskMgr in the right hand pane. Right Click on the DisableTaskMgr item: Click on Delete, confirm that you want to delete, and Task Manager should be available once again. One thing to note is that it's quite possible that if you're in an environment managed by a centralized policy, these settings may have no effect. Your IT administrator may set things up so as to disable Task Manager, and other things as well at the domain level. You'll need to ask them if this is the case.

there are 2 ways..

1. just right click to you task bar (shown below) then click task manager.
2. press ctrl alt del simultaneously, then click on task manager..


cheers!

There is 2 ways to do this.
1) navigate to HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionPolicies. Here open System, DisableTaskMgr, and change Value data to 0, in order to enable Task Manager, or to 1 in order to disable the tool

2) type "gpedit.msc" in the Search box under the Start menu and then launch the tool with elevated privileges, as shown above. Navigate to User Configuration, Administrative Templates; System, Ctrl+Alt+Del Options, Remove Task Manager, and here you can choose between either Enable or Disable the utility

There is a registry hack to enable or disable Windows NT TaskManager. The same registry hack applies to Windows 2000 and Windows XP. Hive: HKEY_CURRENT_USER
Key: Software\Microsoft\Windows\CurrentVersion\Policies\System
Name: DisableTaskMgr
Type: REG_DWORD
Value: 1=Enablethis key, that is DISABLE TaskManager
Value: 0=Disablethis key, that is Don't Disable, Enable TaskManager

As part of the enhanced management available in Windows 2000 and Windows XP, rather than risking a registry change, as an administrator you can enable or disable Windows 2000 Pro or Windows XP Pro's TaskManager using Group Policy Editor. This can be applied to the local policy. Note: if you are trying to override your organizations group policy, you can't. As soon as you re-authenticate to the domain, the domain or OU Group Policy will rewrite the registry setting. But if the TaskManager was accidently disabled or you need to control this item for a set of standalone boxes this is for you:

• Click Start
• Click Run
• Enter gpedit.msc in the Open box and click OK
• In the Group Policy settings window
  • Select User Configuration
  • Select Administrative Templates
  • Select System
  • Select Ctrl+Alt+Delete options
  • Select Remove Task Manager
  • Double-click the Remove Task Manager option

And as I mentioned above, since the policy is Remove Task Manager, by disabling the policy, you are enabling the Task Manager.

Well, your problem seems to be due to a virus attack. Certain virus disable your task manager. To solve this, scan your computer with a good antivirus software and remove the virus. But in most cases you won't be able to restore the task manager with the antivirus application. So the best method is to backup your documents on the the drive where OS is installed and reinstall your OS.

PRESS
CTRL+ALT AND BY HOLDING THESE KEYS PRESS DEL