Whenever Windows is not working properly, most of the time the first thing that I will do is to boot into Safe Mode and see if the problem still persists. If a Windows that will only boot into its safe mode typically has a major problem, such as disk corruption or the installation of poorly configured software or driver that prevents the operating system from successfully booting into its normal operating mode.
Windows in safe mode will have reduced functionality, but the task of isolating problems is easier because many non-core components are disabled (turned off). Safe mode typically provides access to utility and diagnostic programs so a user can troubleshoot what is preventing the operating system from working normally. Safe mode is intended for maintenance, not functionality, and provides minimal access to features.
Although Safe Mode is very useful for troubleshooting computer problems, it can also be used to bypass some security software that autostarts in normal Windows. An example is if you installed an internet monitoring software which restricts your children to use the computer an hour a day, your kid can simple boot in to Safe Mode and use the computer the whole day… There are times we need to disable Safe Mode for extra security.
At first I found a software called NOSafeMode which claims to be able to disable F8, disable Safe Mode and disable Advanced Boot Options in Windows NT based Operating Systems (Including Windows 2000, Windows XP and Windows Vista). It is a simple tool of less than 60KB in size, portable, does not hack or modify the operating system files or registry and can disable ALL keys during boot process so the system boots without any interference. I don’t know whether this tool truly exist or not because I couldn’t find any image or screenshot for NOSafeMode and it cost €19.95. If you have any information on NOSafeMode, please share it with me.
As for the free method, you’ll have to modify your registry, so just follow the steps below on how to disable Safe Mode.
1. Go to Start > Run
2. Type regedit and click OK
3. Navigate to HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\SafeBoot
4. Expand SafeBoot by clicking the + sign and you should see 2 keys with the name Minimal and Network.
5. Rename both of the keys to something else, example, Minimal to MinimalX and Network to NetworkX.

Now if you try to boot in to Safe Mode, doesn’t matter if you select the normal Safe Mode, or Safe Mode with Networking or Safe Mode with Command Prompt, the computer will auto reboot or get a blue screen of death (BSOD).

To enable Safe Mode back, just rename MinimalX to Minimal and NetworkX to Network. I know that this solution is not perfect because if the person knows about this trick, he/she can simply modify the registry to re-enable back Safe Mode. However, it does give some level of protection against an average computer user (or non raymond.cc readers 😛 )
If you’re not comfortable in modifying your system’s registry, I found a very small free tool called Enable/Disable SafeMode which allows you to enable or disable SafeMode. Basically it does the same thing as the above which is modifying the SafeBoot keys. You can also set an application-password to prevent unauthorized access to this tool.

Very easy to use as the tool is pretty much self explanatory. Actually if you can create a Limited User account, you wouldn’t need to use this registry hack because a limited user cannot even access the registry. So this is a solution to those that for some reason don’t want to create a Limiter User.