Windows bit-rot - fact or fiction?

Windows bit-rot - fact or fiction?

Summary: Why do Windows PCs slow down with use? What can you do about it?


Several readers sent me a link to a piece by ExtremeTech's Loyd Case asking me what I thought of the problems he was having with his system:

On the mornings I don't head into the ExtremeTech office in San Francisco, I head downstairs to the basement lab, hit the power button on my PC and monitor, then head back upstairs for shower and breakfast. Usually, my system is powered up and ready to roll when I head back down. It's a pretty speedy setup, too: Intel Core 2 Quad Q9650, 6GB DDR3-1333 and a pair of 7200RPM, 1TB hard drives.

I could, of course, just fire up Vista 64-bit system when I come down to work. But that would mean waiting. Waiting. Waiting for as long a fifteen minutes.

Sheesh! Fifteen minutes! I have a similar system to that which boots up Vista 64-bit in under 30 seconds once I get past the POST. So, what's wrong with this PC? Case offers some insight:

First, I've installed and uninstalled a crapload of stuff. Although Vista is better than XP at managing all the registry hives, things have grown. Right now, my \windows\system32\config folder is 501 megabytes—roughly twice as large as when I first installed the OS.

Ahhh, bit rot, or more specifically, software rot or code rot. This is a subject that I and TalkBack users have touched on many a time in this blog, but I don't think I've ever written about it before in any detail. Time to rectify that.

Is the rot real?

Is code rot real? Some people I've spoken to just simply don't believe that code rot is real and that the idea that a PC gets slower over time is nothing more than an illusion, perhaps as a result of getting used to the speed of the PC or just using it as an excuse to buy a new PC. My take on things is that code rot is indeed real and that a system that was once working fine can be rendered almost unusable in a matter of months or a year. In fact, I'm certain that this factor actually encourages people to trash their old systems and go out and buy new ones.

What causes the rot?

It's important to note that this rot isn't the result of some spontaneous action that occurs to a system. The causes of code rot are in fact pretty mundane:

  • Loading too much software on a system The more software you load onto a system, the more the system has to cope with. Well behaved software shouldn't really have that much of an effect on a PC, but a lot of the software out there isn't well behaved. In fact, software seems to be far more aggressive nowadays than it was say 5 years ago in competing for face-time - firing up when Windows start up, installing itself into the system tray, and generally being a nuisance. And while software is good at installing itself on your system, a lot of it is very poor at uninstalling itself, leaving behind a lot of detritus both in the file system and the registry.

  • Loading duplicate software How many search toolbars, IM apps, email clients and media players do you really need? Ideally it should just be the one. Same goes for security products such as firewall software and antivirus.

  • Free/trial/beta software Just because something's free doesn't mean you really need it on your system! Same goes for software that came free with your system.

  • Old, outdated or incorrect drivers Yep, a big problem.

  • Installing new drivers without uninstalling the old ones ATI and NVIDIA, I'm looking at you!

  • Malware and spyware While malware is can slow down a system, it's not at the top of my list because as a rule it's not the cause of the problem. That said, it's a good idea to scan an ailing system for any nasties that might have found their way into your digital kingdom.

What's the best way to prevent code rot?

Don't do (or at least keep to a minimum) the things I outlined above.

How do you reverse the effects of code rot?

Sometimes. Uninstalling some of the accumulated junk helps, but this can only go so far (thanks to the fact that many programs don't do a good job of uninstalling themselves cleanly).

Case offers this advice:

I could, of course, spend days with a registry cleaner app, carefully checking out the services that load and paring all that down. But when things get to this point, it's usually time to just nuke it from orbit. It's the only way to be sure.

While I question the benefit that registry cleaners can have on system performance, I do agree that any fix that doesn't involve nuking the system can take a long time and there are no guarantees of success.

A good trick if you don't want to reload everything from scratch is to make an image of your system while it's still running fine and go back to that when things have shifted to tortoise mode.

Are other operating systems affected by code rot?

I'm not sure. I have years of experience with Windows. I've had my Mac mini for over a year now and installed quite a bit of stuff on it and yet it feels as fresh as it did on day one. I've got machines running Linux distros too that still feel fresh. I'm tempted to say that code rot is more noticeable on the Windows platform, but without a lot more investigation, I can't say for sure.

Topics: Windows, CXO, Hardware, Software, IT Employment

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  • A fix which does not involve "nuking the system" is best.

    If the problem is coming from residue in the registry, 5 minutes with a registry cleaner will suffice. Try the registry cleaner in CCleaner as a first step. That should be sufficient.

    If not, there's Registry Mechanic and Your Uninstaller to be certain.

    And you might use ERUNT's registry compactor just to smooth out what's left. Also free.

    Of course, "nuking the system"'s main effect for most people is the permanent loss of irreplaceable photos and documents. And even for the people who have good backups, there are all those wonderful hours of updating and reinstalling and reconfiguring.

    Someone who recommends reinstalling the operating system is usually just evading a question.
    Anton Philidor
    • Agreed, but...

      Sometimes nuking the system is the only way you can save it. My friends old Dell (512 MB of RAM, 1 GHz processor, Windows XP Pro) was so clunked up by a half assed install of Norton AV, malware, and poorly written programs, that the only way I could save it was to nuke it.
      The one and only, Cylon Centurion
      • I've lost count of the ...

        ... half-assed Norton AV installs I've come across. I always carry the uninstaller with me ... just in case.
        Adrian Kingsley-Hughes
        • Thank god...

          ...they at least made a decent uninstaller finally. About the only software package Symantec can get right these days.
          • It's a very good thing...

            they have a good uninstaller. Norton is like a huge target that is asking to be attacked. I spend more time using other AV to remove the stuff that has taken over a system with Norton running on it.
          • What?

            I've never had something totally 'take over my system'
            and especially not my Norton software. Sounds like a
            bunch of BS to me, in all honesty.
          • Ok...

            so your experience is the benchmark of all systems I take it?

            I have seen Norton pass over known viruses many times. It is common knowledge among people in the IT industry that no AV product is 100% effective 100% of the time. I have seen plenty systems running Norton and McAfee get infected.

            If yours has not then that is good for you. I hope you remain so lucky.
          • Pity... I could have shown you one such system...

            But I wound up nuking it just the other day. It wasn't mine. One of my client's has a kid who likes living VERY dangerously. The box had pretty much EVERY possible POS known spyware installer, questionable bit of software (Wild Tangent, to name one), and to top it off, every POS spyware/adware "uninstaller" and registry hacker on the planet installed. Needless to say, NONE of it was working.

            Here's a brief description of what the machine was reduced to:

            You plug in the power cord. The machine POSTed properly. It went into the usual Windows boot sequence. It flashed the "Welcome" screen. A wallpaper appeared on the desktop. It had the audacity to say "Your system is infected with a virus. Please install an antivirus." And that was about it. Windows Explorer never loaded. No icons on the desktop. No task bar, no start menu. Not even a mouse cursor. Nothing. If you happened to hit the magic 3 finger salute, a dialog appeared saying "The task manager has been disabled by the administrator."

            DOH! So what I've got on my hands is a 40 lb paperweight. FUN!

            Safe mode - pretty much the same story - except you were given the option to log in as ADMINISTRATOR or HP_ADMINISTRATOR and the wallpaper, of course, wasn't displayed.

            It gets better. If you tried holding down the power switch to shut the machine off, it won't shut itself off. It just goes into sleep/hibernation mode so when you hit the power button again, its instantly back up to that rather annoying wallpaper.

            Removing the hard drive and cleaning it yielded about 20+ viruses, trojans, downloaders and other "fun" stuff - about 300+ copies located all over the place - even on the Recovery Partition. And that wasn't even a complete count. I aborted the scan about 30% of the way through.

            It would have been nice to do anything short of nuking the system. Unfortunately, this kid got PWNED royally. Oh... And the antivirus solution installed on this computer - you guessed it...NORTON Antivirus.

            Now the client's got the task of figuring out what to do... Given the abuse this box has seen, the hard drive is on it's last leg (it's vintage July 2004). And I'm guessing the rest of the system wasn't too far behind. So, it's not only just nuke the drive, but replace it OR replace the entire system. I'm thinking they're gonna replace the whole box.

            If I had my way and could track down the turgid crap dispensers who cooked up the stuff that infected the computer... Let's just say, I'd be able to come up with a few imaginative and excruciatingly painful bits of torture that would no doubt, violate most, if not all of the Geneva Convention... Fortunately, these douchebags remain anonymous.
          • @Wolfie2K3

            Yea... anyone that has no problems with Norton is either a Symantec employee or clearly never done any IT work.

            How much you wanna bet the people at Symantec don't even run Norton on their own systems.
          • Allow me to add another example

            A friend of mine (whose husband, fortunately, is also a geek) recently had her system pwned into unusability. It took him almost a week to clean off, uninstall, find, clean off, find, unhook, clean off (etc, etc) all of the trojans, backdoors, viruses, adware, and other junk that had wormed their way onto the hard drive. All installed despite the up-to-date Norton security software installed on her system.

            And she does *not* browse dangerously.

            I showed them Gizmodo's list of the best freeware at, and with those tools and others, they finally nuked everything nasty off the machine - and, I understand, replaced their security solutions.
          • @ ShadowGIATL: Symantec running Norton...

            Doubt they're using the stock consumer Norton AV. They're likely using their corporate POS... But I'll also guess they've got someone monitoring it 24/7... Along with a TON of other hardware based security measures - spam blockers, firewalls, etc... in place. Given the number of "friends" they've made over the years with their inept products, I would be surprised if someone or someones hasn't tried hacking them from the outside. I'll wager their network is set up tighter that Fort Knox.
          • Be Thankful

            About 3 years ago, I could have said the same thing. I kept hearing about the problems with Norton but I hadn't seen any of them. Hmmm. About that time my system was getting slower so I decided to try to uninstall Norton and try something else. The uninstall when very badly. I called their tech support and at the end of their phone call, which wasn't that long, their advice was to Reformat the HD. Great! I needed to call them for that info?

            I then spent about a month trying to follow varios manual un-install procedures with no success. Oh, by the way, the origional attempt at uninstalling Norton AV changed the boot up time from about 2 minutes to 20 minutes.

            Apparently, Norton did something to the HD because no matter what I did, Norton had left something on there, even after attempting to reformat the drive? After a couple attempts of trying to reboot, I just grabbed another drive off of the shelf and have never let Norton into my office since.

            Unfortunately, this was not the first run in that I have had with Norton AV. I have wasted sooo much time and have trashed a number of systems with Norton AV that I can't belive that they are still in business.

            AND Norton does significantly slow down my systems. McAfee isn't so bad but it is noticable also. I have tried verious registry cleanser and have never seen any noticable improvement in speed but the AV has definately made a huge difference. Apparently, the more applications on a system that there is the longer it takes Norton and McAfee to allow a number of operations to finsh.

            If you still have Norton AV, Good Luck.
          • Norton....

            I used to manage RadioShack stores, and did the majority of store-level tech support for a large swath of Wisconsin...and three pieces of advice that I would give ALL my customers was:
            "don't use Norton sucks.
            If you put Norton Crashguard on your machine, YOU ARE ON YOUR OWN, and, come to think of it,
            Don't use Norton ANYTHING"
          • certainly no fairy tale !

            My XP notebook had Norton on it when purchased.
            BUT it let in more nasties than it stopped !
            The first few times on the internet with that machine - hooooooee the number of gremlins that got in...
            I replaced it with what I thought was another "good" AV - McAFFEEs ... how wrong, this did find a heap of junk which Norton let in, but had its problems too.
            I finally decided to give the Free version of Grisoft's AVG a go. This proved to be the best resolve, as the amount of rubbish the other AVs left behind, which AVG discovered was annoying to say the least.
            After a few years with AVG, I am presently trying BitDefender - the best part is a lower overhead, it seems to use less resources than all the previous AV apps, besides being a good AV .

            [ AND, get 3 or 4 popular anti-adware apps as companions to the AntiVirus app. - and update and run these regularly as well ]
          • I have

            I've also seen Norton bring a system to its knees on its own. Although I've heard the new version is better, I'm not ready to trust it. And I know that the earlier versions left its tentacles so deeply in the OS that it was necessary to download a special installer to remove all (or at least most) traces. They may have fixed these problems, but the criticisms of earlier versions have been well-deserved.
          • I think the numbers speak volumes here. (nt)

            If you didn't get the meaning there... Norton sucks by majority.
        • Its a wonder

          Just how bad that program can be... Reason number one why I don't use it....
          The one and only, Cylon Centurion
          • Evil is as evil does...

            The real wonder is how the heck Norton AV keeps winning all these damn Editor's Choice awards on pretty much EVERY site that reviews such things when it sucks hard boiled rotten eggs.


            Out of all of the computers I've had to "nuke from high orbit" in the past 5 years, Norton AV or it's bastard cousin - Symantec AV - was installed on EVERY one of them, except for one.

            And that one exception was one of my own boxes that had a number of hardware issues. The motherboard was on it's last leg, it was vintage 2003, had a fairly nasty amount of bit rot and was too slow to do some of the tasks I wanted to do. I figured after 5 YEARS, it deserved to be backed up and paved over with the fresh hardware upgrade. Oh.. and it had Panda Antivirus installed on it.

            The others in question were doozies.

            10 of them were on a network with Symantec's "corporate" solution. It was installed on their server. But somehow, the "automatic" live updates... Let's just say they were NOT automatic. In fact, they never happened. WTF? Panda always updated itself without any problems. Avast! always does it's thing automatically. Trend Micro's automatic. In fact, pretty much every other antivirus - with a current license - does it's automatic updating - well - automatically. 6 months later, every box on the network, including their servers were compromised beyond usefulness.

            Another one had an expired Norton license - it didn't even bother loading and running.

            I'm due to be shipped another computer from an old client who's got Norton on his box. He's been hit by a few rather nasty bits and I'm likely to have to nuke it as well. <sigh> Another one with a hosed system. At least, he keeps an online backup.

            So yeah... I gotta wonder just how Norton in it's various incarnations keeps getting Editor's Choice. It's fairly heavy on system resources. It never seems to do it's job. If you happen to not pay on time, OR have issues with renewal, it drops dead leaving you unprotected.

            The only answer that makes any sense - money talks... They buy the EC with advertising or other "contributions"...
          • Thanks for the heads up.

            I knew about most of what you said, but in the first sentence was "wild tangent". Just last week I uninstalled a 868M trial off a friends new Toshiba laptop. I did not know that it was notorious spyware but just felt it was taking up a lot of space for a trial. That brand new laptop also had Norton of course and I got rid of that and put on Avast. How about all of that Cisco and Toshiba software that seems to be duplicating other programs, should I get rid of them, too? It is not my computer so want to be conservative. Truthfully, though the owner is so clueless that I could do anything.
            My own computer is a 9 year old Emachine and since I installed XP over ME, I have never reinstalled the OS and had only one BSOD that was last summer when I put Chrome on it for a day. Now I do very little compared to you guys but I do check out a lot of free and trial software, but get rid of them after looking and I do occassionally use a registry cleaner. My biggest problem in the last year was getting rid of an Adobe installation that would not uninstall. It was a known problem from Adobe and there was step by step instructions to clean the registry. I am an old timer and remember keeping my W95 clean out of neccessity, with a 1G HD, but of course it was much easier
          • Gotta love them...

            Wow this talkback turned into hate Norton didn't it. Well deserved though, as I hate coming across systems with it loaded.

            The free version of AVG find more bad stuff then Norton.