Why Do I Have to Restart the Computer After Updates?

[disney_mommy]

I have a question I've been wondering about for some time and I hope someone can answer it for me here...

After I update my computer or add or delete a program, why does the computer have to restart? Is it some sort of refresh thing that has to happen?

Is it more complicated than that? Does something have to be turned off to finish the installing/uninstalling process?

Why hasn't someone out there come up with some sort of way to do those things without having to restart?

Okay, that's my deep thought for the day.

[RickyMaveety]

Originally Posted by disney_mommy

I have a question I've been wondering about for some time and I hope someone can answer it for me here...

After I update my computer or add or delete a program, why does the computer have to restart? Is it some sort of refresh thing that has to happen?

Is it more complicated than that? Does something have to be turned off to finish the installing/uninstalling process?

Why hasn't someone out there come up with some sort of way to do those things without having to restart?

Okay, that's my deep thought for the day.

My thought is that you are talking about a Windows PC?? The need to reboot (or restart) the computer is because Windows stores all of its program information in a "registry" which has to have changes made to it when you install, update, or remove a program from the machine.

Windows can't finalize changes to the registry while it is in use, and it is in use the entire time that your computer is running. So, in order to make the changes, it needs you to restart the computer so it can update the registry.

[Who are you?]

Ricky, the registry can be updated at any time, no reboots are needed for that.

On current windows versions most software installations/uninstallations shouldn't require a reboot. Those that do ask for one usually need to delete or modify files that are in use by the system or some application.

The usual culprits are drivers for hardware that is currently being used, files used by windows explorer to display some additional information and services that aren't stopped before uninstall (this last one really is an error/laziness by the person who made the uninstaller)

[ilovejedd]

Originally Posted by Who are you?

On current windows versions most software installations/uninstallations shouldn't require a reboot. Those that do ask for one usually need to delete or modify files that are in use by the system or some application.

The usual culprits are drivers for hardware that is currently being used, files used by windows explorer to display some additional information and services that aren't stopped before uninstall (this last one really is an error/laziness by the person who made the uninstaller)

Yep. For some Windows Updates, there are protected files and/or critical system files in use that needs to be replaced, hence requiring a reboot.

By the way, In was able to play a bit with a Hackintosh and it was pretty much the same when updating. I updated from OS X 10.5.2 to 10.5.5 and that required a reboot. Same thing when I updated QuickTime.

[RickyMaveety]

Originally Posted by Who are you?

Ricky, the registry can be updated at any time, no reboots are needed for that.

On current windows versions most software installations/uninstallations shouldn't require a reboot. Those that do ask for one usually need to delete or modify files that are in use by the system or some application.

The usual culprits are drivers for hardware that is currently being used, files used by windows explorer to display some additional information and services that aren't stopped before uninstall (this last one really is an error/laziness by the person who made the uninstaller)

They are if you want the install/uninstall to work properly. I've had to go in and hack the registry so many times for improper entries as a result of a bad installation or program removal it isn't even the tiniest bit funny. And, they are most often an artifact of not rebooting after allowing a program to make a change to the registry.

I mean, I've only been building and repairing computers for 25 years now, but it's always possible that all those years of crawling around in the registry are naught but a figment of my imagination.

Let's try it this way. Information regarding drivers, program installation and uninstallation, as well as which driver each program is to use is stored in the registry.

Most often the message you will get from Windows on installing or changing a program is "The system needs to be restarted for the changes to take effect."

That is because, although you can write to the registry, the system will not recognize changes to the registry .... until you reboot. The registry is the first thing that Windows looks at when it checks to see how each program is supposed to be running, what drivers it is supposed to use, whether it is to run in the background at start up ... etc., etc.

Now, ilovejedd, you are talking about "Windows Updates" .... that is not what the original poster was asking about. It is true that there are critical files that need to be replaced in an update of an operating system. I'm sure that is also true of updating the operating system on an Apple PC. However, what the original poster was talking about was not system updates, but installing or removing programs and why you need to reboot a PC when you are doing that. A Windows PC will not "see" changes made to the registry until the system is rebooted.

Apple does not use a registry system. Why an Apple PC would need to be rebooted on an operating system update is not exactly a mystery, even to me.

[wodin]

Originally Posted by RickyMaveety

I mean, I've only been building and repairing computers for 25 years now,

As have I! The second most useful adage I have found (after RTFM) is “When in doubt, reboot!” You can never tell what might be hanging around in memory.

[HarryT]

Originally Posted by RickyMaveety

That is because, although you can write to the registry, the system will not recognize changes to the registry .... until you reboot.

That's not entirely correct. The registry is implemented as a shared memory-mapped file in Windows, and any changes are instantly visible "globally".

The issue is that most processes only read their configuration data from the registry when they start up, so even though the data may have changed subsequently, those changes will not actually be read until the next time the process starts - ie at the next reboot.

All processes in the system are sent a notification that registry data has changed, and are recommended to re-read their configuration data on receipt of such a notification. Processes which do this can smoothly handle registry changes. Many processes, however, ignore such notifications, and hence will only read changed registry data on reboot.