Windows 7 Slow Transfer/Copy Speed

I just tried copying a folder from a DVD to a second partition in Windows 7 RC (7100) and it's taking forever...

The directory contains ~42,000 files, mostly just a few kilobytes in size. Total size of content being copied is 2.96GB. The file copy operation has been going on for almost two hours now and says it has 45 minutes remaining... Transfer speed is averaging ~400KB/s. The target hard-drive is a 7200rpm SATA with 32MB cache. The DVD drive is a brand new Pioneer SATA. All IDE/ATA channels have UDMA enabled in device manager.

At first I thought it might be a hardware issue (and I suppose it's still possible) but doing a Google search shows slow transfer speeds have been a very common problem in Windows Vista which never got resolved, and I've found a few people reporting the same thing in W7RC, so I'm not alone.

For reference, my rig is an AMD AM3 810 Quad-Core with 4GB DDR2 RAM.

The problem seems to be caused by some operation that executes on each file being copied, so the more smaller files you copy, the more you get affected. Some suggest it's due to new code in Explorer and that copying from a command-line prompt is much faster. I suspected it may be something to do with Windows Defender or some other service that runs on a per-file basis.

I'll do some testing to see if I can narrow down on the issue and post back more results later. If anyone has a solution, please let me know.

UPDATE: After further testing, the cause of the slow copy I described appears to be simply due to the slow seek speed of DVD drives. I tested by copying the same fileset on my laptop and the internal DVD drive was sounding like an old floppy disk. You could literally hear the head moving up and down to find each file. I haven't tested this on an XP system, but I'm guessing it would be just as slow. 

I should also point out that I was using a DVD-R. If memory serves me right, -R stores data as one long spiral. So to find a specific file, the head must traverse the spiral until it finds the start marker. The +R format stores data in a structure more similar to a typical hard-disk (circular tracks sub-divided into sectors). So the file index table stores which track the file is located on and in which sector such that the seek head does not need to scan the whole DVD to find each file. That is, a DVD+R is a better choice for storing many small files (better at random access), whereas a DVD-R is typically better for movies where the information is read sequentially from start to end.

I tried re-producing the problem on my laptop by copying large sets of small files from one HD partition to another on my solid-state drive (negligible seek time) and experienced no issues whatsoever (50,000 10KB files copy in around 140 seconds).
I thus don't believe this to be a Windows 7 issue anymore, but rather a hardware limitation.

UPDATE 2: I haven't done any additional testing by myself, and haven't really used many optical disks on my systems lately. But from all the comments below, and the fact that this is the most popular article on my blog, maybe there's a problem here after all.

UPDATE 3: There's a few things to be aware of when copying files and noticing slow speeds:

  1. CD-R and DVD-R may degrade over time. I haven't researched this, but from my own experience, many DVDs I burnt years ago are now hard to read. I expect they have shorter life-spans when compared to factory-pressed discs.
  2. Laptop/netbook CD/DVD drives are likely to be slower than desktop drives. So let's compare apples with apples.
  3. USB Flash pen drives have notoriously slow write speeds, and have been getting slower and slower over the last 5 years. Chances are an old 1GB stick you may have hanging around will be twice as fast or faster than a new 16/32GB flash stick. 
  4. Windows 7 optimizes USB Flash disks for stability so that you won't loose any data if you plug it out without using the Eject tray icon. It does this by disabling write caching, which exasperates the slowing write speeds of new-gen sticks. You can change this by choosing to re-enable write caching, at the risk of loosing data if you don't eject properly.


  1. I have xp on one machine and win 7 on another. I copied the same dvd on both, and it took 16 minutes on the win 7 machine. The xp machine took about 5 minutes...

    I think this has to do with win 7

  2. "I think this has to do with win 7".
    It has. Windows 7 assess _all_ files to copy before it actually begins, just to show off the amount of time it will take to copy or move the files. Very annoying.

  3. Here's the microsoft answer, first blame 3rd parties and then try some useless activity like 'safe mode'

    why don't they just admit copy and transfer speeds in Windows 7 are vastly inferior to Win XP?

  4. I have noticed horrible transfer speeds disc to disc in Windows 7 after updates

    1. Exactly...It took till 2012 but they got me too... Now I need to find someone who can unspike my win 7

  5. I'm blaming this on W7 based on the evidence and testing I've done, which matches up with other conclusions registered here. My problem was slightly different in that I noticed massive lags in booting up CD/DVD's - even just reading ther contents in Win Explorer. On XP response was almost immediate. On W7, it reads the disc then spends five minutes or more seemingly digesting the information, with the hard drive activity light on constantly. I've read some reports of conflicts with graphics card drivers, so that's where I'm going next. I'll keep you posted.

    FYI, System is:
    Win 7 HP edition
    Pentium dual-core E5300 @ 2.6GHz
    3Gb installed RAM,
    Nvidia GeForce 9500GT (2Gb)

  6. I'm currently copying from my RAID 0 array to a laptop hard drive. Many, many small files... A. It's moving at about 960KB/s, B. I'm taking a major performance hit while doing so.

  7. Guys, I'm having the same problem with my two PC's, one laptop with SSD and one desktop with RAID 0, so extremely fast both of them. WHen I copy files through the network, wired or wireles,, I get speeds of about 1 to 2 Mbs, ridiculous. I blame it on Windows 7, hence before that I had XP machines and they were fast, so the problem isn't in the network itself. Why Microsoft doesn't fix the problem since it exists since Vista?

  8. I transferred approx. 42,000 files from 6 DVDs on my Widows 7 machine in a little over 12 hours. The same transfer on an inferior Windows XP box took less than 6. From what I can tell this is definitely a Win 7 issue!

  9. I have the same issue ripping a DVD on the same exact machine with XP 7 Minutes, on Windows 7 30. I have to OS because I cannot make the switch to 7 fully. This is another reason why.

  10. When I right click ANYTHING in explorer and tell ti to send to my E drive(burner drive) I get speeds typically around 686-688 KBps twenty minutes to burn a 1.1 gig dvd with nothing but 256 files, 32 folders. That is not nearly as good as XP. What happened here Microsoft?

  11. i have a very simple system one big (fast) disk,
    2 OS winXP and windows 7 on it.

    when i need to copy / delete many files from one place to another (on the SAME disk) i reboot to winXP to do it.

    windows7 is copy /delete (a most basic and critical OS function i would say) is crippled.

  12. I am Having the exact same issue with all usb and firewire external drives. Starts great and then slows to a drip. My new usb3.0 drive seems okay.

  13. another example here, contents of a DVD ROM taking about 20 mins to write to hard drive, previously with XP on same hardware 5 mins. eagerly awaiting the solution ...

  14. I think I just hit lucky because some new DVD-RW drivers had just been released for my Optiarc 7230S DVD+RW drive just after my Feb post. I installed the new drivers and I haven't had a problem since them. GL all.

  15. I'm currently copying a 6 GB file from one drive to another at an amazing 587 kb/s. It's going to take 2 more hours (in addition to the 2 it has already taken) at this rate. Total BS.

  16. I really like Windows 7, but the file transfer speed is insanely slow. WTF Microsoft???

  17. Again same problem here. I thought it was hardware so I u/graded optical firmware and mobo drivers. No change.

    My only complaint with this OS. It can't be that hard to patch MS???

  18. Richard:

    Was searching for solutions and found your page. Without meaning to sound disrespectful, I think you mean "exacerbate", not exasperate.

    Great posts otherwise.

  19. For some of you a ramdisk will fix the problem, But MS will get wise to this and send updates that infect the ramdisk as well.

    I got away with it for several months.


  20. I just got hit with this problem today. All my backups are on DVD+RW... if I ever have to rebuild my system from backups using Win7 I'll be here for months. A 528MB folder on DVD+RW copied to my desktop with XP takes 6 minutes. With Win7 I gave up after an hour. 70KB/sec transfer speeds? Hasn't this been patched yet?

  21. Disable TCP AutoTuning and Receive Side Scaling > 7 or Vista

    Open an elevated command prompt with administrator rights.
    Type the following commands and press Enter (the second command on RSS is optional):

    netsh interface tcp set global autotuninglevel=disabled

    netsh interface tcp set global rss=disabled

    Should be fast after reboot

    1. Disabling TCP AutoTuning and Side Scaling is only for network transfers and does not help or apply to reading and copying data from DVD to HDD.


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