The stability of an operating system is almost always compromised when vendors of third-party products try to overwrite its system files with versions of their own, sometimes customised, files. This can cause problems with other applications on your system that share these files - especially if an older file tries to replace a newer one.
Microsoft has tried to combat this in Windows Me by including a utility that acts as bodyguard to these important files, which are mostly DLL (Dynamic Link Library) files. The System File Protection utility is enabled by default, and it can't be disabled. It works stealthily at all times and will replace files - if needed - instantly, without you even knowing about it, whenever protected system files are renamed, replaced or moved.
Show ME protected files
By default, you will not be able to view your system's protected files, as they bear hidden and system attributes. Even if you have indicated that all hidden and system files be shown under the Folder Options-Tools View tab, you will still not be able to see them. To make all files viewable, including the protected files - for backup purposes, for example - click the View tab, and uncheck the "Hide protected operating system files" box.
If you're interested in seeing what changes the System File Protection utility has already made, a log of its "activity is kept on your system and can be viewed by going to the C:\Windows\System\sfp directory and opening the sfplog file.
Keep Me informed
If you don't like the secrecy with which System File Protection works, the Microsoft Knowledge Base has instructions on how to receive a pop-up message every time a protected file is replaced. To enable this, you will have to do some poking with Regedit. Make sure you back up the Registry before you make any changes, by going to Registry-Export Registry File. Launch Regedit by selecting Start-Run and typing regedit. Navigate to the following key:
On the right-hand pane you should now see a value called ShowPopups. Double click this value and change the value data from 0 to 1. You will need to restart the computer before this change takes effect.
If one of your protected system files becomes corrupted or unusable, you will have to extract and replace the file manually from the Windows Me installation disk. You can do this two ways.
It is best to boot up your computer in Safe Mode, which you can do by pressing the
Alternatively, if you receive an error message saying you can not replace the file in question, you will have to perform extraction from a DOS prompt using a Windows Me boot disk. (You can make one from the Add/Remove applet in the Control Panel.) Boot up your system using this disk and type extract at the DOS prompt. You will see a list of switches and instructions on how to use this command (I recommend you read this carefully in order to become proficient with the command).
You can be prompted on startup, via a menu, to boot up the system normally or in Safe Mode. To enable this menu, go to the System Configuration Utility and from the General tab click on the Advanced button. Place a check mark next to "Enable Startup Menu", and you're set.