Service TrustedInstaller.EXE permanently active taking up to 50% CPU resources

In my limited experience, I've seen svchost for a long time on core-2-duo and i3 cpus, associated with Windows Update, and sometimes I wonder if it's ever going to stop.

I think I'm repeating myself on this thread, but the svchost will finish whatever its doing, sometime, some day.  Don't give up.  Let it keep working while you're away from the computer.  Worse for people with "older" cpus and performing a lot of catch-up on their updates.

If it's a laptop, make sure the air inlets and outlets are unblocked, i.e., not laying on a rug with the cooling fan sucking up a lot of dust into the ducts; maybe install Core Temp to monitor the cpu temperature, and check Intel.com to see what the maximum temperature the cpu can tolerate, so you can quantify that the cooling system is working sufficiently as designed, especially since this situation may drive your computer harder than anything else you do.

You want to assure that your computer doesn't get fried by Windows Update, because then you'll really get angry.

svchost finishes on newer computers a lot faster, probably because of all the new instruction-sets that are added to the newer processors.  But when I did a fresh install of Win 7 on a modern i3 laptop with 8 GB of ram (more ram than I've ever had in one computer), there were a million windoze updates.  Telling windows to take care of it automatically was a mistake; it maxxed the cpu AND the ram usage, and the computer seemed to freeze for a couple of hours.  I don't know if it would have finished on its own, but finally I lost patience, and forced exit out of the offending process (windows update? svchost?).  I restarted the computer, and before it went back into its overload state, I switched the setting on Windows Update for it to "notify me, only," and I would download and install manually.  I re-sorted the updates by size, and for the bigger downloads, I only did a few at a time.  For the smaller downloads, I did up to a dozen at a time, or so.  I monitored the ram usage in Task Manager, and if the ram got up to 100% usage, I knew I was updating too much at one time.

I assume that i7 computers with 32 GB of ram are able to perform three years of windoze updates all at once.  One day, I hope to try it, out of curiosity.  Unless I'm so entrenched in Linux that I don't care anymore.

I have been on (benevolent) websites, like Crucial Technologies, that can scan the insides of a client computer and determine what CPU and memory the client computer has inside.  So, it seems obvious to me that Micro$oft's Windows Update could do the same thing, and take steps automatically to avoid grabbing 100% of the computer's resources, and especially avoid freezing the computer for an indeterminate period of time, by regulating how many updates it will perform at once. 

They could add some functionality to automatically regulate the barrage of windows updates.  But they don't.  And since Microsoft doesn't accept users' feedback on their domain, there's not really anyway to suggest it to them.  The only feedback at our disposal is either buying their product or getting something else.

I think, since every new MS operating system has started requiring a significant learning curve -- i.e., avoiding big learning curves are unavoidable anyway, then next time I might as well go for Linux.  I think I'll google for "love Linux Windows," to see which distribution has the most love among former Windows users.

Thank you for your comments.

You are correct in saying 'just let it continue to scan and some day it will get them all' - another poster had advised the same and yep, it did finally see the 222 Important updates and actually tried to install them.

Most of those failed (likely not needed after all) and several did install properly.  Since then no amount of scanning would get any others and when it did get to the results only Optional updates were in the list.

The Optional updates were taking an extremely long time to download - even the disk light was out for quite some time.  I finally killed the update effort and then it showed it had downloaded a partial update but showed Cancelled.  Ah well...

I then picked one very tiny update of 168kb - I left the download run for over 30 minutes and it never completed in that time.  Since this was so tiny it should have completed download AND install in about 30 seconds.

Even when I don't go to and start Check for Updates the Win Update PROCESS starts up, takes the CPU and memory to high usage and keeps them there without ever downloading or installing updates.  This is not normal behavior and performance is severely impacted while they are kept high constantly.

All my computers get Windows updates without issue except for this laptop.  This laptop has been updating flawlessly for years until some problems started in June 2015.  Again, not to repeat myself - there were network awareness issues which I resolved by upgrading to Win 7 Pro but the Update problem did not get resolved.

At this point I will likely wipe the drive and do a clean install next week!  The laptop hardware is good and quick so it is worth the expense and effort though I started considering a new laptop due to frustration.  Once the laptop is healthy I will likely upgrade to Win 10 Pro.

Since upgrading to Win 7 Pro the laptop runs fast; file downloads are quick and never an issue - the only problem remaining is with Win updates and after a week of chasing it down we have not come to a resolution so a clean install is the next step.

Again, thanks for your comments.  SevenForums is an excellent venue to get help from the community and posters like yourself help to make it worth the effort.  Keep it up.

I upgraded from Win 7 Home to Win 7 Pro...

Is it the same computer (not the same problem) in this previous thread of yours and/or your "Me, too!" post in this recent thread?

Yes, only one computer involved - a Sony VAIO laptop. 

I replied to your other question post like this.

Heading towards a clean install next week.