When attempting to use ‘msconfig’ a message appears that ‘An Access Denied error was returned while attempting to change a service. You may need to log on using an Administrator account to make the specified changes’. When I click OK msconfig closes. I am the only user on the computer, and have administrator privileges. The only unusual event prior to this issue occurring was the unsuccessful installation of the latest version of QuickTime, followed by several equally unsuccessful attempts to remove all traces of QuickTime from the computer. The computer is running Windows XP Home Edition.

If this error occurs when attempting to modify (enable/disable) items on the ‘Services’ tab of msconfig you don’t need to worry. This is likely because you are attempting to disable a required Windows service and it is not allowing you access to make this change (rightfully so, since it is likely to be a vital system service). Even so, it is not a good idea to modify the services through msconfig. Given the design of this utility, it is possible for the user to disable services which are essential to the computer booting. It is a very dangerous thing to modify services through msconfig, and should not be done through this method. If you wish to modify which services start on startup, this should be done through the Services control panel. To open this control panel, go to the ‘Control Panel’ and open ‘Administrative Tools’ > ‘Services’. Alternatively, go to the ‘Start’ menu > ‘Run’ and type ’services.msc’ (without the quotes) and click OK. The Services control panel should not allow you to disable services which are vital to boot Windows.

Should the problem occur when attempting to open msconfig, it could be caused by a program running in the background. Some users have reported ZoneAlarm can cause this problem. To check this theory, disconnect from any networks (e.g. the internet) and shutdown ZoneAlarm. Check if the problem persists. If the problem stops, you may need to add ZoneAlarm to the trusted zone on the computer. Open ZoneAlarm, then go to ‘Program Control’. Click the ‘Programs’ tab. Find ‘System Configuration Utility’ in the list of programs and give this program Trusted access (e.g. allow the utility access to the trusted zone).

However, if ZoneAlarm is not causing the problem, the next most likely cause is some other program running in the background interfering with msconfig. Again, make sure your computer is disconnected from any networks (since you will be closing any security software running on your computer). Close down all visible running background applications, then use CTRL-ALT-DEL and click the ‘Processes’ tab. Sort the processes by ‘User Name’. If this column is not displayed, go to the ‘View’ menu > ‘Select columns’ and tick ‘User Name’. Close all the non-essential processes running under your user name. You should be able to close all processes except ‘explorer.exe’ (the Windows GUI) and ‘taskmgr.exe’ (the Task Manager you are currently using). Once the processes are closed, try running msconfig and, if successful, restart the computer (to restart all the processes) then close visible applications and processes one-by-one, each time checking whether you can open msconfig. This will allow you to narrow down the application or process causing the issue.