Windows just lost a > 30GB file. Edit: Some files grew in size too!

[Ketchup]

While it sucks that Windows lost the file before completing the task, I had an old Netgear router that did this. New router meant no more issues. In my particular case, that problem alone did not cause the replacement, but it sure did help.

 

[Ichinisan]

Don't cut/paste on files that are important to you. Copy/paste, then delete the original on successful copy.

Tried it. Here's what happened:

I noticed that some folders had a slightly different file size. Narrowed it down to a couple of small files. The copy is larger than the source.

This sucks.

[edit]
First pic is the source. Second pic is the copy.

When I view the bad copy with Notepad++, it shows 32 normal characters followed by lots and lots of "nul" characters.

 

[Ketchup]

Tried it. Here's what happened:

[edit]
First pic is the source. Second pic is the copy.

When I view the bad copy with Notepad++, it shows 32 normal characters followed by lots and lots of "nul" characters.

Is this from the pc to the external hard drive again? Are they running different files systems?

 

[Ichinisan]

Is this from the pc to the external hard drive again? Are they running different files systems?

It's the same scenario as before. Source drive is connected to the network (Seagate GoFlex Home 2TB). Not sure of the file system. I have to access the network share with alternate credentials because my Windows username is slightly different than the username I set up on the drive. When I create a new user on the drive to match my Windows username, it doesn't show me the same folders where I've already copied almost 2TB of files. Once I get everything offloaded, I'll find a way to initialize it and set it up with the same user / password as my Windows user account. I've mounted it network drive S:.

I have noticed quirks with the network drive before. I don't remember exactly what it was, but files or folders with certain characters in the filename would disappear. I couldn't even view / move the files with the command line, but I could right-click an Explorer window and undo.

Destination drive is Western Digital 3TB USB3 attached to USB2 controller, file system is NTFS.

 

[Elixer]

Tried it. Here's what happened:

I noticed that some folders had a slightly different file size. Narrowed it down to a couple of small files. The copy is larger than the source.

This sucks.

[edit]
First pic is the source. Second pic is the copy.

When I view the bad copy with Notepad++, it shows 32 normal characters followed by lots and lots of "nul" characters.

One drive has 4K blocks, the other has 1K. That means, that a small file (say under 1K) will fill up 1 block (4K) on one drive, and 1 block (1K) on the other drive.

 

[Ketchup]

One drive has 4K blocks, the other has 1K. That means, that a small file (say under 1K) will fill up 1 block (4K) on one drive, and 1 block (1K) on the other drive.

That's what I was getting at as well. I think you nailed it.

 

[CZroe]

One drive has 4K blocks, the other has 1K. That means, that a small file (say under 1K) will fill up 1 block (4K) on one drive, and 1 block (1K) on the other drive.

The why is the size 4K and not just the size on disk? Also, why does it now have null characters appended to it? He mentioned this to me the other day. IIRC, he said it was an MD5 file. Strange. I wonder what a file comparison would reveal about the other files that don't appear larger/smaller.

 

[Ichinisan]

One drive has 4K blocks, the other has 1K. That means, that a small file (say under 1K) will fill up 1 block (4K) on one drive, and 1 block (1K) on the other drive.

That's what I was getting at as well. I think you nailed it.

No. That would affect the "size on disk." It would not affect the file contents.

 

[Nothinman]

Tried it. Here's what happened:

I noticed that some folders had a slightly different file size. Narrowed it down to a couple of small files. The copy is larger than the source.

This sucks.

[edit]
First pic is the source. Second pic is the copy.

When I view the bad copy with Notepad++, it shows 32 normal characters followed by lots and lots of "nul" characters.

That would make me very leery to store anything important on that thing.

 

[Ichinisan]

That would make me very leery to store anything important on that thing.

Thing is, I'm not sure which drive was responsible. The source, or the destination? Maybe neither is responsible and Windows is at fault?

 

[Ketchup]

Thing is, I'm not sure which drive was responsible. The source, or the destination? Maybe neither is responsible and Windows is at fault?

I tried this on my server, which is going over the network, but to and from SATA drives. I do not have this issue, I don't think. The values are the same on the properties tab (4b, 4kb), but if I pull up the folder it is in, I see 1k. So glad today we worry about GB and TB, not kb.

 

[wirednuts]

http://technet.microsoft.com/en-us/magazine/2009.04.utilityspotlight.aspx

http://download.microsoft.com/downl...c359cc0842/HoffmanUtilitySpotlight2009_04.exe

/thread

 

[lxskllr]

Thing is, I'm not sure which drive was responsible. The source, or the destination? Maybe neither is responsible and Windows is at fault?

My money would be on the network drive. Maybe something squirrelly with the logic board? Can you disassemble it, and hook the drive up as an internal in your computer? That would help narrow it down, but I think it has to do with the USB.

 

[Nothinman]

Thing is, I'm not sure which drive was responsible. The source, or the destination? Maybe neither is responsible and Windows is at fault?

I've never known Windows to pad files with null bytes and the fact that it's aligned to the cluster size implies it happened at the filesystem level on the destination. I also find your inability or unwillingness to consider that NAS to be the problem mildly entertaining. If it was Windows doing it then you would be seeing it a lot more often and most likely your PC would be crashing or at least otherwise acting oddly as apps were given data with extra nulls when they were only expecting one for EOF.

 

[Ichinisan]

I've never known Windows to pad files with null bytes and the fact that it's aligned to the cluster size implies it happened at the filesystem level on the destination. I also find your inability or unwillingness to consider that NAS to be the problem mildly entertaining. If it was Windows doing it then you would be seeing it a lot more often and most likely your PC would be crashing or at least otherwise acting oddly as apps were given data with extra nulls when they were only expecting one for EOF.

I didn't say that I don't suspect the network drive. Ever since this file grew in size after being copied, it seems most likely. Still, I expect there to be some CRC checks or something to tell me that it didn't transfer correctly.

 

[Nothinman]

I didn't say that I don't suspect the network drive. Ever since this file grew in size after being copied, it seems most likely. Still, I expect there to be some CRC checks or something to tell me that it didn't transfer correctly.

I believe the CRC errors you're thinking of are generated by local storage drivers, not Windows or Explorer. AFAIK Windows doesn't do any extra error checking/correction when writing to anything and just assumes that as long as WriteFile(), write(), etc complete and return the correct number of bytes that the data was committed successfully. Comparing an md5 or sha1 checksum on each file or chunk of data would slow it down significantly.

 

[MrChad]

Verifying that a file reached its destination correctly is not a simple problem to solve, especially with caching and other features on modern drives. If the destination drive does not report any errors when writing the file, how is Windows supposed to know that the file may not have been copied successfully?

http://blogs.msdn.com/b/oldnewthing/archive/2012/09/19/10350645.aspx

 

[notposting]

Anything important like that, I would copy first, then delete (and do it through right click dragging, because I am pro like that).

Also, the ghost of Ballmer wants you to go pay for another rental.

 

[kache]

Why doesn't windows move the moved file to the trashbin, instead of deleting it directly?

 

[Ketchup]

Why doesn't windows move the moved file to the trashbin, instead of deleting it directly?

What what I have seen, when moving a file to a network location, the Recycle bin is out of the picture. Same when deleting a file from a network location.

OP, have you tried reformatting the drive and trying again? And for Pete's sake, do a copy first. Much faster and safer, as others have mentioned.

 

[Ichinisan]

Well, it looks like the new 3TB drive is the culprit.

I'm out of storage and I needed to start using the 3TB drive, even though I don't trust it. I've wasted hours copying files and performing fc /b file comparisons. I still have over 1.5TB that I need to copy. Well, I was on third really-large file when the comparison encountered differences between the source and the destination. Deleted, copied again, performed comparison again and it passed.

This sucks.

I have the worst luck with hard drives. I buy a massive capacity drive for backup / archival and it just starts trashing files. Ugh! How can they actually sell products like this?