Interesting idea, but Windows should produce a clear error message when failing to copy a file larger than 4GB to a FAT32 partition.
-
Welcome to the new forums! Please read this first. For known issues we are working to resolve, click here.
External HDD question (Windows OS)
- Thread starter Satyaa
- Start date
Sean Nelson
Veteran Member
Is it "stuck" no matter how long you let it sit? For example, if you were to let it sit there for an hour, would it eventually finish?
One common cause of confusion is that when you copy files to a drive, Windows will normally try to cache writes to the drive. (I believe it doesn't do this for USB FAT drives by default, but it does for NTFS drives).
So when you start a copy you see the progress bar moving along at a pretty good clip that's limited only by the speed at which it can read the file from the source drive. That can be very fast indeed if the source drive is something like an SSD.
However if the target drive is slower, then at some point if the file is large enough Windows will run out of RAM memory to cache the writes into. At that point the transfer suddenly slows down to the speed of the target drive, and the progress bar seems to stop moving (or moves only very slowly). If the output drive has a very slow connection (i.e., USB 2) then it can get "stuck" this way for a long time as the data trickles out to the drive. It'll be faster for a better connection (i.e., USB 3) but it can still seem quite slow compared to data coming from an SSD, for example.
Attempts to do something else with the target drive (i.e., open an Explorer window to see what files have been copied) can be impacted as well since the I/O requests needed to access the drive get queued up behind the ones already issued for the copy.
If the "stuck" condition you're seeing eventually clears itself if you leave it sit for long enough, then I'd suspect that this is what you're seeing.
OK. I misread that. I'll pay attention to how much of RAM is used next time this happens.
Thanks
Yes, several of my video files on that drive are over 4GB. Possibly as large as 28GB if I remember correctly.
I left it there for at least an hour several times. At least one time, I left it overnight.
When the program gets stuck, say when it's 45% done, from that point, it is at that stuck file without further progress. The estimated remaining time keeps increasing from few minutes to hours and days. I know it's not going anywhere.
Understood.
Correct. When I use FreeFileSync to backup specific files/directories to a 2TB external SSD, it takes a few seconds for few GB files.
It has nothing to do with the file size in question though. Sometimes, large files are copied at the beginning of the copy process. when it is stuck, it could be a small (relatively), say a 30MB .NEF file.
The only way to clear it is to stop the copy job (the program up to a minute to respond and gracefully stop). I run Windows Disk Optimization. If that doesn't progress, then I run disk error check.
I go back to FreeFileSync and everything moves at a good speed again.
Thanks
LynniePad
Veteran Member
- Messages
- 4,109
- Solutions
- 12
- Reaction score
- 1,267
Check out the Robocopy/help information. It looks complicated, but if you want to see my preferred options, send me a PM. Robocopy works by interrogating the file attributes, e.g. “Archive” comparisons.
I have my data separated into several main folders…
- Old data (refreshed occasionally).
- Photos (updated regularly and periodically backed up).
- Current data (updated frequently and also backed up quite often).
”Backing up” means a simple Windows copy to external HDDs.
Last edited:
Carey Brown
Veteran Member
No, you may have a chip with a flaky bit. A mem-check program does a few read-write cycles to every byte of ram you have and verifies that what was written matches what was read.
Sean Nelson
Veteran Member
I had an intermittent RAM problem once that manifested itself as failures to verify my backups. I spent a lot of time diagnosing that problem because I assumed at first that it was some sort of disk issue. Eventually I tracked it down using a memory testing program. Since then I've made a point of only buying systems with ECC memory.
Robert Zanatta
Veteran Member
Try using resource monitor to view the activity for your drive. It should show which file(s) are open, current data transfer rate, disk response time, etc.
OK. I will check memory
OK. Thanks
David Lal
Veteran Member
I have encountered something similar making hard drive bit images using Macrium, from Paramount Software in the UK. One of the HDDs I was trying to back up would repeatedly fail about 22% into the operation.
The cause turned out to be bad sectors on the (1tb) source disk. I replaced the source disk for the grand sum of GBP £18 (Ebay, lightly used , perfect secondhand SATAIII 1tb disk). Lo and behold, problem gone, perfect backups.
You may find a piece of free software called CrystalDiskInfo useful for checking your source disk.
Last edited:
David Lal
Veteran Member
The download page is here:
https://crystalmark.info/en/
You'll get a report on your disk's or disks' condition, like this:
Don't confuse Crystal Disk with Crystal Mark. Good luck.
Last edited:
Robert Zanatta
Veteran Member
In case no one has mentioned it, chksk /r. It will take some time to run.
David Lal
Veteran Member
Good point Robert. I run chkdsk like this:
> chkdsk c: /f /r /x
However, prior to doing that I run:
> sfc /scannow
That specifically checks and tries to repair areas of the disk used for system files where bad sectors would be an extra problem. This is all very time-consuming and sometimes one needs to go round the loop a couple of times. When a HDD is dying bad sectors can recur within days.
I use FreeFileSync on my M1 Mac, but I run it everyday so usually only a few megabytes or a few gigabytes each time. You might try changing to a daily schedule so that the copies are smaller.
On my PC I use the free Syncback to do the same. I like it much more than FreeFileSync, but Syncback is not available for Macs.
On my PC I use the free Syncback to do the same. I like it much more than FreeFileSync, but Syncback is not available for Macs.
When I open disk properties in Windows Explorer, go to Tools tab, and select 'Error Checking', isn't that running chkdsk?
Thanks
David Lal
Veteran Member
No, I don't think so - at least not in its full incarnation. I believe running it (or clicking the tools button) inside windows merely causes it to report on your bad sector situation, but does not actually fix anything.
When chkdsk c: /f /r /x is run in a Command or Powershell window a program stub is deposited which will be run at the next boot in an attempt to map out the bad sectors so that the operating system does not try to use them.
Keyboard shortcuts
- f
- Forum