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There are several things to look at. One is folder size. If files are accumulating in the folders, then Windows Explorer has to do more work to enumerate the list of files.

I have 32-bit Windows 7 on a machine with 4 GB of RAM. When I open Windows Explorer and click on a directory such as My Documents, the list of files is becoming slow to load and a green bar moves from left to right at the top of the pane. It used to be instant, but now it's getting slower and slower. An indexing problem perhaps? I've defragged the drive and I've tried CHKDSK, which reported the drive clean.

In this excerpt from Answercast #64, I look at several factors that could be making Windows Explorer load slowly.

Slow Windows Explorer

There are a couple of different of possibilities here that come to mind right off the bat.

Surface defect

One is that even though CHKDSK reported that the drive is clean, it is possible that there is a surface defect on the drive that is causing the drive to read more slowly.

In other words, the operating system as it tries to read a marginal sector (or a number of marginal sectors of data) has to try again and again and again to finally read the data. That of course adds up to slowness when you see it.

The thing I would do first would be to run CHKDSK /R. /R does a surface scan and presumably will detect any bad sectors and mark them as being no longer available for use. It will actually move the data around as well. So, if things are working for you now, if CHKDSK /R finds anything, then you should actually have no data loss.

Hard disk repair

If it doesn't and it still feels like a hard disk problem, I also often recommend SpinRite.

SpinRite does what I call a "low-level format" without losing any data. What that boils down to is it will go out and read and rewrite every sector on your hard drive, making sure that it can. If for whatever reason it has trouble reading the data, it will do everything in its power to recover that data from a sector and then either write it in that same place (a fresh copy) or write it somewhere else on the disk. And as the CHKDSK did, mark the sector that it had problems with as bad.

Unfortunately, SpinRite isn't free. I believe it's like $95. That obviously starts to compete with the cost of a new hard drive... though you might actually start looking at the cost of your time to do the replacement of a hard drive or something like that.

Overloaded directories

The other couple of things that aren't quite as dramatic, but still could impact the performance and the speed at which Windows Explorer might display a directory listing are simply the number of files.

You haven't indicated how many files there are, but it takes longer to show more files.

If files are accumulating (even if hidden files are there), then Windows Explorer has to do more work to enumerate the list of files that it's about to display and to present things like the list and the appropriately sized scroll bars.

Now, obviously, one thing you can do is see if there are a bunch of files... move some somewhere else. In other words, create sub-folders and organize your data a bit so not everything is in a single folder.

How much is "big"?

When I talk about "large numbers of files," what do I mean?

Easily a thousand files, I think, could cause this kind of an issue.

Potentially (depending on your system) as little as a hundred files in that folder could have a negative impact on performance.

It's one of those things that does grow over time, as you add more and more files to the folder. So check out the number of files that you've got in there. See if you don't want to reorganize things a little bit - if there are a large number of files.

Detail view

Finally, the other thing that you haven't mentioned is which View you are using.

Interestingly enough, if you are using something like an Icon view or a Thumbnail view, Windows Explorer has to do a lot more work for every file that it's going to display. It actually has to open the file, read the icon out of it, or produce a thumbnail from it.

Especially... if the thumbnail cache has been turned off, that can take a fair amount of time and is again one of those things that would increase as the number of files increase in that folder.

The alternative (and to be honest, the way that I run completely; only) is to select the View menu and select Details. I only look at file details.

You won't get a pretty picture. You won't get an icon. You'll get the file name, its size, its date, a couple of other things, but that will be very quick - because Windows Explorer then doesn't have to go out and grab all those icons, or create all those thumbnails, or what have you.

So those are the kinds of things I would point you at:

  • Potential hard disk problems

  • The number of files you have in that folder

  • The view setting that you are using within Windows Explorer

The last two obviously are really quick to check so I'd suggest you do those first and then I'd start looking at potential hard disk issues.

Article C5950 - October 24, 2012 « »

Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

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October 26, 2012 9:08 AM

There might be a lot of what I call 'trash' files on the disk that CCleaner can get rid of. My sister had never heard of CCleaner and her machine was filthy with them. It ran way faster after I setup and ran CCleaner for her.

October 28, 2012 3:52 AM

(1)CCleaner is good.
(2) Spinrite is too expensive{for me anyway} for often very mixed results. I would rather spend the money on a new hard drive.
(3) For a speed test, disable all the start up items {type msconfig in search box} These can be re enabled at any time later if required.


Nigel Lord
October 28, 2012 12:11 PM

I think also we just have to accept that Windows Explorer is just slow. I gave up on it a couple of years ago and started using the free xplorer2 from Zabkat. As well as offering multiple panes to make dragging and dropping easier it is just so much quicker than Windows Explorer.

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