Question File Transfers To/Between USB Drives Stop (or crawl)

Jan 17, 2022
6
2
10
Hi,

This is my first time posting here. I've read many similar threads to mine, but have tried all the suggestions I can find and just can't find an answer to this problem.

I recently bought a new laptop running Windows 10 (a Lenovo Legion 5 Pro). However, it has developed a problem where I cannot copy large quantities of data (more than a few GB) between USB drives, or from the internal SSD to a USB drive. This problem occurs with any USB drive, regardless of type or formatting. Initially, the file transfer appears to begin successfully at normal USB 3 speeds for the drive type (and small file transfers are successful), however, after a while the speed begins to become unstable, then plummets down to just a few KB/s, then, most often, stops entirely, reaching 0 bytes/s and never increasing. I have tried a lot of things to solve this, but none of them have made any difference. These include:

  • Restart PC
  • Unplug all other USB devices
  • Quit Google Drive
  • Disable antivirus (Bitdefender Free)
  • Quit backup software (EaseUS Free)
  • Try different USB drives (HDDs and flash drive)
  • Try different USB ports
  • Copy a different set of files.
  • Read from external drive instead of write - seems to read fine, but won't write anything large
  • Airplane mode
  • Safe mode
  • Disable Remote Differential Compression
  • Disable Windows Search
  • Try from a different user account
  • Check Event Viewer - couldn't find anything that seemed relevant
  • Check Task Manager and Resource Monitor - couldn't see any untoward activity
  • Copy between two external drives - seems to be less prone to the problem than when copying from internal SSD, but not immune.
  • Increase priority of Windows Explorer process
  • Uninstall antivirus
  • Disable Windows Defender
  • Check for corrupt system files - checked and repaired by DISM and SFC
  • Is compression switched on on external drives? - no
  • Disable USB selective suspend
  • Update system
  • Run Chkdsk on all drives
  • Uninstall Google Drive
  • Update/reinstall drivers - updated via Windows Update with optional updates, reinstalled USB drivers
  • Disable drive indexing
  • Try 3rd party file copier - tried Teracopy: exactly the same problem
  • Run Memory Diagnostics - no problems found
  • Run Hardware and Devices Troubleshooter - nothing relevant "fixed"
  • Check "Optimise Drives"
  • Uninstall backup software
  • Try a different drive format in external drive - tried exFAT (previously NTFS): same problem
  • Test many small files vs one large - one large (~250GB) file causes no issues. Many smaller ones cause the problem to occur.
There are a few things I haven't tried yet, some of which I wish to avoid, if at all possible.
  • Test network file transfer. This is what I'll try next.
  • Installing another OS on a new partition and try testing it from there (just to rule out a strange hardware issue).
  • Update to Windows 11. I might try this.
  • System Restore. I'd really prefer to avoid this, as I've only just solved some major problems that I've been having with Google Drive, and this could cause more problems in that regard.
  • Reinstall Windows from scratch. I'd prefer to avoid this to save all the work of reinstalling everything.
I've read a lot about this issue online, and it seems as though it may be a problem that has existed since Windows 8, but there never seems to have been a solution. I cannot be sure of this, however.

I'd be really grateful for any suggestions anyone can give!!

Thanks.

Derek.
 
Last edited:
Are the drives warm or hot to the touch? Is it possible that they are overheating? If you fan the drives with your hand or a similar object, does that improve performance?

(This will sound crazy but I bought a battery powered hand held fan to cool my usbs and external drives and it seems to help).
 
Jan 17, 2022
6
2
10
Thanks everyone for your responses! :)

Are all of the plugged in USB drives drawing power directly from the laptop?

If possible try using an independently powered USB 3.0 hub.

Connect the hub to the laptop and the USB devices to the hub.

Good idea, but unfortunately the problem still occurs when using an independently powered HDD, or a powered USB hub, so I don't think this is the issue.


Are the drives warm or hot to the touch? Is it possible that they are overheating? If you fan the drives with your hand or a similar object, does that improve performance?

(This will sound crazy but I bought a battery powered hand held fan to cool my usbs and external drives and it seems to help).

The drives aren't particularly warm, and I have run some of the same drives happily for years on another computer with no issues. The problem also even occurs with flash drives.
Your fan idea certainly isn't crazy if it solves your problem!! :)

Thanks.

Derek.
 
Last edited:
Jul 14, 2021
35
3
45
I'm a complete newbie so I'm going to give an observation rather than a solution. I too have experienced extreme speed decreases when copying files to various external drives. It often stops completely only to continue 5-10 minutes later. I currently have 3 external hard drives and 3 external SSDs attached to a USB hub on my laptop, which has it's own SSD. All the drives are self-powered. But I've noticed similar problems even when there's only a single external drive.

The only clue I have is that the problem seems worse when my laptop's C drive is low on space. It seems like the C drive is somehow used as a buffer during file transfers, even when I'm transferring from one external drive to another external drive. Indeed, when my C drive is running low, I sometimes get a "there's not enough space" error even when there's [much] more than enough space on the destination drive to copy the selected files. The last clue is that the "not enough space" error only occurs when copying multiple files, even when they are small files. Copying one huge file from one external drive to another has never produced the error, even when the file size far exceeds what's available on the C drive.

In summary, I have no answers for you, but would suggest that you free up some space on your primary drive and see if the problem persists. And see if the copying resumes after 5-10 minutes of stopping. Good luck.
 
Jan 17, 2022
6
2
10
I'm a complete newbie so I'm going to give an observation rather than a solution. I too have experienced extreme speed decreases when copying files to various external drives. It often stops completely only to continue 5-10 minutes later. I currently have 3 external hard drives and 3 external SSDs attached to a USB hub on my laptop, which has it's own SSD. All the drives are self-powered. But I've noticed similar problems even when there's only a single external drive.

The only clue I have is that the problem seems worse when my laptop's C drive is low on space. It seems like the C drive is somehow used as a buffer during file transfers, even when I'm transferring from one external drive to another external drive. Indeed, when my C drive is running low, I sometimes get a "there's not enough space" error even when there's [much] more than enough space on the destination drive to copy the selected files. The last clue is that the "not enough space" error only occurs when copying multiple files, even when they are small files. Copying one huge file from one external drive to another has never produced the error, even when the file size far exceeds what's available on the C drive.

In summary, I have no answers for you, but would suggest that you free up some space on your primary drive and see if the problem persists. And see if the copying resumes after 5-10 minutes of stopping. Good luck.

Thanks very much for your suggestions.

I have left it quite a while, and I wasn't previously experiencing this problem (transfers were fast all the time), but I will try leaving it a very long time and see what happens! It's certainly worth a try!

My C drive isn't low on space, but I will check to ensure that there's more free space than the size of the files I'm trying to copy.

Question that has not been asked - Make/model/size of these flash drives?

The models of drives that I have tried are:
  • 2x Toshiba Canvio Basics 4TB 2.5" External HDD (USB 3.0). (Both brand new).
  • Western Digital Elements 1TB 3.5" external HDD (USB 2.0). (Over 10 years old).
  • Kingston Datatraveler 32GB flash drive (USB 2.0).

Unfortunately it doesn't seem to matter what drive I use!!
 
Jan 17, 2022
6
2
10
Hi,

I've tried a few more of everyone's suggestions today. These are the results...

  • Copying one very large file (~250GB) is successful. No problems with the transfer at all. Copying lots of smaller files causes the problem to occur. This must offer a clue as to the cause I feel.
  • Ensuring there's more free space on the C drive than the total size of files that I'm trying to copy unfortunately made no difference.
  • Leaving it a long time - I left it hung for around 2 hours (the transfer should've only taken 5-10 mins). The transfer never resumed.
I haven't had time to test network transfers yet, but this'll be next.

I've also noticed that while copying between two external drives does still frequently stop, weirdly, it seems less prone to the problem than copying from the internal SSD to an external drive, but is by no means totally immune. I have no idea why this would be!

Just an observation - which may be completely wrong - but it feels as though some process, or low-level part of the system is getting hung up in the background, and the file copy is waiting on this to complete whatever it is doing (which it never does) before being able to continue. Unfortunately, Task Manager, Resource Monitor etc offer no clues. As I say though, this is just guesswork, and not based on any real evidence, so don't take too much notice of this!!

Thanks everyone for your suggestions so far.
 
Last edited:
Jan 17, 2022
6
2
10
Hi,

It's been a long time since I last updated this thread, but I'm writing to say that I have finally solved the problem!!

Firstly, I tested network file transfers (SMB). These also all failed in the same way.

As a result, I decided to install Ubuntu to test if the issue still occurred on another OS. Ubuntu could copy the files reliably, but did so very slowly for some reason (11MB/s instead of 130MB/s in Windows), but I think this is a separate issue, as the files copied successfully every time, but took a long time (and this issue also seems to be well documented online). Consequently, I booted back into Windows and tried one other thing that I hadn't thought of, which was to disable (and re enable) window auto tuning and receive side scaling. Shortly after I'd done this (and rebooted), file transfers started working again!!!

Considering the various things I tried, it seems that the most likely explanation is one of a few possibilities: personally, I think either disabling window auto tuning, and then reenabling it, or doing the same for receive-side scaling was probably the solution. However, it's hard to say for sure, as when I first tried the file copy after disabling them, it didn’t make any difference. However, I didn’t try again after reenabling them, and I also didn’t restart the PC when I tested this. Consequently, it’s possible that either the toggling/reenabling or the restart were needed and this did in fact fix it. The other possibilities are that: it fixed itself somehow (not an update though as updates are currently switched off), it had something to do with shrinking the C volume in order to make room for Ubuntu (incl. deleting all System Restore points and temporarily disabling the pagefile), it was just somehow a result of the numerous restarts needed to get Ubuntu up and running, or it had something else to do with installing Ubuntu. However, I do think the auto-tuning thing is the most likely. I have no idea why this would have fixed though as, as I understand it, auto-tuning and RSS are only supposed to affect network file transfers, but perhaps it’s all tied up somehow.

Anyway, hopefully that'll be helpful to someone else who may have this same issue.

Derek.
 
  • Like
Reactions: SamNYC and Grobe
Jul 14, 2021
35
3
45
Hi,

It's been a long time since I last updated this thread, but I'm writing to say that I have finally solved the problem!!

Firstly, I tested network file transfers (SMB). These also all failed in the same way.

As a result, I decided to install Ubuntu to test if the issue still occurred on another OS. Ubuntu could copy the files reliably, but did so very slowly for some reason (11MB/s instead of 130MB/s in Windows), but I think this is a separate issue, as the files copied successfully every time, but took a long time (and this issue also seems to be well documented online). Consequently, I booted back into Windows and tried one other thing that I hadn't thought of, which was to disable (and re enable) window auto tuning and receive side scaling. Shortly after I'd done this (and rebooted), file transfers started working again!!!

Considering the various things I tried, it seems that the most likely explanation is one of a few possibilities: personally, I think either disabling window auto tuning, and then reenabling it, or doing the same for receive-side scaling was probably the solution. However, it's hard to say for sure, as when I first tried the file copy after disabling them, it didn’t make any difference. However, I didn’t try again after reenabling them, and I also didn’t restart the PC when I tested this. Consequently, it’s possible that either the toggling/reenabling or the restart were needed and this did in fact fix it. The other possibilities are that: it fixed itself somehow (not an update though as updates are currently switched off), it had something to do with shrinking the C volume in order to make room for Ubuntu (incl. deleting all System Restore points and temporarily disabling the pagefile), it was just somehow a result of the numerous restarts needed to get Ubuntu up and running, or it had something else to do with installing Ubuntu. However, I do think the auto-tuning thing is the most likely. I have no idea why this would have fixed though as, as I understand it, auto-tuning and RSS are only supposed to affect network file transfers, but perhaps it’s all tied up somehow.

Anyway, hopefully that'll be helpful to someone else who may have this same issue.

Derek.

Thanks for the update and info. When I was having similar problems, I decided to bypass Explorer altogether and use an app to copy/move files. The fastest by far is a Japanese freeware, FastCopy. The interface isn't pretty, and some of instructions are poorly translated, but the program copies and moves files without a hitch. As I type this Files Explorer just crashed for the nth time, but FastCopy continues moving 50+ gb of files with no interruption.