Windows Boot Magic: What does the Registry Key for COMClassStore for?

February 5, 2010 12:04 PM

What does the Registry Key for COMClassStore for? Why does it make my machine boot up much faster?

Some guy at work has been raving about how setting COMClassStore in the windows registry makes his boot time just 2 minutes rather than the usual 10 minutes for our work machines (that's the average boot time for most of our laptops due to some encryption crap).

Question is, what does this registry key do, and will we be able to live without it?

I've already disabled it to test, and I can't lie. It does make booting much faster without any noticeable changes to the functionality of my machine.

Thanks.

posted by onich to computers & internet (9 answers total)

Sorry, mental grammar/spell check does not work on Fridays.
posted by onich at 12:09 PM on February 5, 2010

This registry key tells Windows whether or not to download missing com components at boot time. Here's a bit of article about it.

I can see why it might speed up boot time since you would skip checking com dependencies at boot time to see if there are any missing. It shouldn't cause an issue until you try to use some app that is missing a com component.
posted by Babblesort at 12:13 PM on February 5, 2010

Hi Babblesort, thanks for getting back to me. Would you be able to tell me what com components are? What sort of applications use com components?
posted by onich at 12:17 PM on February 5, 2010

Alternatively, will Windows or the app that needs an updated com component be smart enough to tell me if I need to update it or something?
posted by onich at 12:21 PM on February 5, 2010

Well that's kind of a deep subject. I'll try to give a very shallow description of it...

In essence COM is a Microsoft defined way of building software from separate reusable pieces. Reusing the pieces allows programmers to focus on a particular problem and not rebuild the wheel for every new program. In general when you install some software many separate pieces are installed.

If one of the pieces is missing the application won't run and should give you some kind of error message. How clear this is depends a lot on the quality of software development that went into the thing you are trying to use. You probably won't run into an issue with missing components if you are using mainstream programs with built in installers and a normal Windows install.

Tweaking stuff in the registry can produce significant changes in Windows. It's also possible to really FUBAR your system if you aren't careful and don't know what you are doing. Microsoft deliberately makes the registry a poorly documented and controlled thing.
posted by Babblesort at 12:35 PM on February 5, 2010

That's pretty much the explanation I'm looking for, Babblesort, so thank you. So bottom line, will it be ok if I leave COMClassStore off? I don't really install many programs in my machine. Everything I need is pretty much already installed. The only thing I can think of that this might impact is if the programs I use need some updates or something

Will it be an acceptable work around to just turn the setting on, then reboot, whenever I install a new program? If so, how do I handle updates?
posted by onich at 12:45 PM on February 5, 2010

Sorry, I missed the error message part. So generally, I'd probably know if I need an updated COM component? Will turning it on then rebooting and re-installing the impacted problem a workable solution? Or would this workaround cause unknown issues as well?
posted by onich at 12:48 PM on February 5, 2010

I'd say not to worry about it unless you get programs behaving strangely or complaining of missing files. Then turn it back on.
posted by Babblesort at 12:50 PM on February 5, 2010

You made my day, Babblesort. I won't mark the thread as resolved in case somebody else wants to chime in. But I do have piece of mind to continue to have it disabled.
posted by onich at 12:54 PM on February 5, 2010