iPad File corruption on copy to external storage

[sparksd]

Over on Reddit, I've been in a conversation with a user who was seeing photos being corrupted on copy from his iPad to a Samsung T5 SSD. He was seeing around 5% corruption in just over a hundred files copied. He suspected the T5 was a problem but I have not trusted Files with large numbers of copies, having seen issues before. As I have the same drive, I ran my own test. What I wrote to him:

I just ran a test, using 105 photos (50-50 Canon RAW & processed JPEG) in a folder in On My iPad in the Files app. I copied those files to my 500GB T5 SSD. Checking them on my Win10 laptop, I found that 4 had been corrupted and were unreadable. I ran the same test but using a 500GB Western Digital spinning drive; in this test 1, file was corrupted. Both drives are formatted exFAT.

Other findings: When plugging the WD drive into the laptop, I got a msg that the drive had problems and needing to be repaired, which I did. This did not occur with the SSD. Also, on both drives, the size for every copied file says 4KB while the files are actually 7MB - 25MB in size (size shows correctly in image viewing app). But if I look at the properties for the containing folder, it shows the correct size for the aggregate of the images.

My conclusion is what I stated earlier - the Files app is immature and has problems when copying large numbers of files to external storage.

Edit: The OP over on reddit reformatted to macOS Extended journaled and the corruption stopped. So it appears the issues lie with interaction with exFAT drives. Which sucks as I don't own any Mac devices.

Edit 2: One more data point - I have the FileBrowser for Business app and it supports external storage. I executed the same test there and no files were corrupted. In addition, on Win10, the files show the correct size.

 

[AutomaticApple]

My conclusion is what I stated earlier - the Files app is immature and has problems when copying large numbers of files to external storage.

We can only hope that they improve the Files app in iPadOS 14.

 

[Ludatyk]

My conclusion is what I stated earlier - the Files app is immature and has problems when copying large numbers of files to external storage.

Yeah, it’s definitely immature. Copying files takes longer than usual and I feel this year was of iOS 13 tock process of the iPad. With iOS 14 being the tick process improving on the new features that was added to iOS 13, especially mouse support and Files app.

 

[sparksd]

Did more tests today. I used a USB-C hub with my T-5 SSD and Western Digital HDD attached to it. I copied the same 105 files in my earlier test (a new, clean copy of them) from the HDD directly to the T5 using the Files app. Attaching the T5 to a Win10 laptop, none of the files appear corrupted but for every file an additional file with the same name but with "._" appended to the beginning of the file name was created. Each of these files showed up in Explorer as being 4KB in size. Again, both drives are exFAT.

Second test, again with two drives in a hub, using FileBrowser for Business, I copied all 105 files to the iPad from the HDD, into a folder in FileBrowser. From that folder, I used FileBrowser to copy those files to the T5 SSD. Copy was all good, with no "extra" files. Unfortunately, with FileBrowser you can access only one of the external storage devices attached to the hub at a time, necessitating the intermediate copy to the iPad.

Files sucks.

 

[secretk]

Did more tests today. I used a USB-C hub with my T-5 SSD and Western Digital HDD attached to it. I copied the same 105 files in my earlier test (a new, clean copy of them) from the HDD directly to the T5 using the Files app. Attaching the T5 to a Win10 laptop, none of the files appear corrupted but for every file an additional file with the same name but with "._" appended to the beginning of the file name was created. Each of these files showed up in Explorer as being 4KB in size. Again, both drives are exFAT.

Second test, again with two drives in a hub, using FileBrowser for Business, I copied all 105 files to the iPad from the HDD, into a folder in FileBrowser. From that folder, I used FileBrowser to copy those files to the T5 SSD. Copy was all good, with no "extra" files. Unfortunately, with FileBrowser you can access only one of the external storage devices attached to the hub at a time, necessitating the intermediate copy to the iPad.

Files sucks.

Files definitely is not mature enough to be used like that. I am curious what prompted you to do these tests? I mean did you have to copy lots of files to the iPad for something or you just wanted to test the boundaries of the Files app?

 

[sparksd]

Files definitely is not mature enough to be used like that. I am curious what prompted you to do these tests? I mean did you have to copy lots of files to the iPad for something or you just wanted to test the boundaries of the Files app?

I got involved in a discussion over on Redddit about a problem a user was having - they thought their SSD was faulty so I wanted to doublecheck with the same SSD. But this isn't an unusual use case - it replicates what I - and many others - would want to do to back up files from a camera card to another drive while on travel. In fact, 105 photos from a single days shooting would be small. And exFAT is fairly standard for camera card format. This means it may be better to take the laptop as iPadOS is not trustworthy for this simple operation. Or use the FileBrowser workaround that I found to work.

 

[secretk]

I got involved in a discussion over on Redddit about a problem a user was having - they thought their SSD was faulty so I wanted to doublecheck with the same SSD. But this isn't an unusual use case - it replicates what I - and many others - would want to do to back up files from a camera card to another drive while on travel. In fact, 105 photos from a single days shooting would be small. And exFAT is fairly standard for camera card format. This means it may be better to take the laptop as iPadOS is not trustworthy for this simple operation. Or use the FileBrowser workaround that I found to work.

Thanks for the insight! Oh yeah man there are days (if I say I am on a trip) that I can take up to 100/200 photos a day and even more. And if the trip is few days I could have up to 500 - 800 photos you know. And yeah naturally once I am back I would want to transfer them to my processing device to process the RAW files.

 

[sparksd]

Thanks for the insight! Oh yeah man there are days (if I say I am on a trip) that I can take up to 100/200 photos a day and even more. And if the trip is few days I could have up to 500 - 800 photos you know. And yeah naturally once I am back I would want to transfer them to my processing device to process the RAW files.

Exactly, a normal use case. I ran the tests multiple times with different devices and on some I was seeing 5% file corruption. Another issue is that sometimes the drive has to be repaired when disconnected from the iPad and connected to a Windows laptop. In the past, I would do this file backup using a RAVPower wireless FileHub and it was flawless - I could plug both an SD card and drive into it and do a photo backup. That's another option I may fall back on. But it's not like I'm doing much travel now ...

Now another new thread on exFAT issues -

iPad Pro ruins SSD every time I plug it in

It’s exFAT, thanks for the link, I’ll have a look.

forums.macrumors.com

 

[SimonMScott]

I’ve noticed that some quirks happen with external SSDs for me.

I exclusively use Samsung T5 1TB SSDs.

If I plug in a drive that I’ve previously used on my MacBook then it seems to take longer to recognise the drive on my iPad Pro (2020) and also doesn’t show up in Files the next time I plug it in for almost 5 minutes?! Almost like it has to re-index the drive or something odd going on?

Recently, though, I bought a brand new Samsung T5 1TB and ONLY used it/plugged it in to the iPad Pro exclusively. I’ve been having no issues since with that drive.

So, definitely something going on with MacBook formatting of the drives that doesn’t play nice with Files on iPad Pro...

Strangely though the T5s are supposed to be “plug and play” without formatting required on most systems so who knows!

 

[sparksd]

Reran the test under 13.5, copying 105 JPEG & RAW images from the Files app to an exFAT-formatted SSD (Samsung T5) and 8 were corrupted in the transfer.

 

[zaytex]

I have also been having this issue transferring photos from SD to iPad and then to 1tb T5 ssd. I’ve tested both through the hub (SD card straight to ssd) as well as SD -> folder on iPad -> t5 ssd later on. The issue has persisted no matter how slowely or from where I move the files. About 10% of the jpegs end up visually corrupted (with bit loss? It looks like youve opened the image in a text editor and deleted a few lines) or totally un-openable on my desktop PC. Going to try the workaround listed above - pretty big issue for my workflow and would be keen for a permanent solution.

 

[sparksd]

I have also been having this issue transferring photos from SD to iPad and then to 1tb T5 ssd. I’ve tested both through the hub (SD card straight to ssd) as well as SD -> folder on iPad -> t5 ssd later on. The issue has persisted no matter how slowely or from where I move the files. About 10% of the jpegs end up visually corrupted (with bit loss? It looks like youve opened the image in a text editor and deleted a few lines) or totally un-openable on my desktop PC. Going to try the workaround listed above - pretty big issue for my workflow and would be keen for a permanent solution.

Yeah, I've completely quit using the Files app for anything and use FileBrowser for Business for general file management.

 

[sparksd]

Others having issues with exFAT storage -

https://www.reddit.com/r/ipad/comments/gs43nj

 

[Ludatyk]

Others having issues with exFAT storage

I wonder though.. what's the best format to use with the iPad for transferring files?

 

[sparksd]

I wonder though.. what's the best format to use with the iPad for transferring files?

It sounds like HFS+ has worked well for some who have posted. But you need a Mac ...

 

[steve62388]

There was another member here on the forums that did extensive testing transferring files and encountered corruption too. I can’t remember the final outcome. See if you can find the thread.

 

[Taodon]

I have a similar case with no fix

Tl;dr

Filming with Mavic Air 2 and copying files from SD card to SSD corrupts the files and adds stutter. The original files are okay. No matter how I copy, there’s no change, even from one SSD to the other.

Drohne

Folder

1drv.ms

Good day people,

I have a problem, something I can’t solve by myself.
Tried everything that came to my mind... but let’s start at the beginning.

Two weeks ago I got myself a sweet DJI Mavic Air 2, fantastic drone and tool.
Recording 4K 60fps h265 and using LumaFusion is a great combination and the iPad Pro 2018 has plenty of power.
Filming was so much fun that I had to upgrade my disk space.
Bought a SSD, Samsung T5 with US. 3.1, so plenty of speed.

I started copying my files directly from SD to my SSD and noticed that the files were jittery while playing. I tried everything: new SD cards, new adapter, different apps even tested every codec setting on the drone. But the files kept stuttering, and I tried everything.

After a while I noticed that imported video files from SD to the photos app work flawless. But copying files back to the SSD creates the stutter. No matter how and what I copy, the files being written on the SSD have the stutter and artifacts.

So there has to be a problem with the copying but I can not explain it.
Importing the files to the Photo app and then moving them to SSD causes stutter too. Copying on PC keeps the files intact so it’s not a hardware problem.
Here is an example

Drohne

Folder

1drv.ms

The SD files are the original and fine files from the drone
The kopiert are the copies.

Can someone please help

 

[sparksd]

I have a similar case with no fix

Tl;dr

Filming with Mavic Air 2 and copying files from SD card to SSD corrupts the files and adds stutter. The original files are okay. No matter how I copy, there’s no change, even from one SSD to the other.

Drohne

Folder

1drv.ms

Good day people,

I have a problem, something I can’t solve by myself.
Tried everything that came to my mind... but let’s start at the beginning.

Two weeks ago I got myself a sweet DJI Mavic Air 2, fantastic drone and tool.
Recording 4K 60fps h265 and using LumaFusion is a great combination and the iPad Pro 2018 has plenty of power.
Filming was so much fun that I had to upgrade my disk space.
Bought a SSD, Samsung T5 with US. 3.1, so plenty of speed.

I started copying my files directly from SD to my SSD and noticed that the files were jittery while playing. I tried everything: new SD cards, new adapter, different apps even tested every codec setting on the drone. But the files kept stuttering, and I tried everything.

After a while I noticed that imported video files from SD to the photos app work flawless. But copying files back to the SSD creates the stutter. No matter how and what I copy, the files being written on the SSD have the stutter and artifacts.

So there has to be a problem with the copying but I can not explain it.
Importing the files to the Photo app and then moving them to SSD causes stutter too. Copying on PC keeps the files intact so it’s not a hardware problem.
Here is an example

Drohne

Folder

1drv.ms

The SD files are the original and fine files from the drone
The kopiert are the copies.

Can someone please help

Try a 3rd party app other than Files for the copy - fixed (worked around) the issue for me. I'm convinced that wrt exFAT storage, Files is broken.

 

[Taodon]

I will try the business app next, the app File Explorer did not help

 

[Taodon]

Tried the business file app and still the same problem...
bleh

 

[sparksd]

Tried the business file app and still the same problem...
bleh

When you do the copies, are you copying multiple files at a time? If so, have you tried moving just one at a time? I don't see that a much of a viable alternative but the test could help narrow down the issue.

 

[Taodon]

I tried copying one and multiple files of different size

 

[sparksd]

I tried copying one and multiple files of different size

The internals of the iOS interface with external storage suck (at least wrt non-Apple-formatted storage) - buggy and undependable.

 

[GNEF]

I bought MAVIC AIR 2 and for the same reason I bought SSD. But I noticed issue in copying videos from iPad Pro to SSD - corrupted video files or video files dropping frames. I thought it's something wrong with SSD, so I returned the SSD.

Then I bought external WD HDD, but it was not recognized by iPad or MAC because it's NTFS...

Then I followed guidance to reformat to exFAT in a PC, then it won't be recognized still by iPad or MAC

Today I tried to reformat this HDD to "Mac OS Extended" format using a Mac.

Problem solved!!!!!

But I can't access this HDD on a PC any more

So in summary, it's the compatibility issue between Files app and exFAT in my assessment

I have a similar case with no fix

Tl;dr

Filming with Mavic Air 2 and copying files from SD card to SSD corrupts the files and adds stutter. The original files are okay. No matter how I copy, there’s no change, even from one SSD to the other.

Drohne

Folder

1drv.ms

Good day people,

I have a problem, something I can’t solve by myself.
Tried everything that came to my mind... but let’s start at the beginning.

Two weeks ago I got myself a sweet DJI Mavic Air 2, fantastic drone and tool.
Recording 4K 60fps h265 and using LumaFusion is a great combination and the iPad Pro 2018 has plenty of power.
Filming was so much fun that I had to upgrade my disk space.
Bought a SSD, Samsung T5 with US. 3.1, so plenty of speed.

I started copying my files directly from SD to my SSD and noticed that the files were jittery while playing. I tried everything: new SD cards, new adapter, different apps even tested every codec setting on the drone. But the files kept stuttering, and I tried everything.

After a while I noticed that imported video files from SD to the photos app work flawless. But copying files back to the SSD creates the stutter. No matter how and what I copy, the files being written on the SSD have the stutter and artifacts.

So there has to be a problem with the copying but I can not explain it.
Importing the files to the Photo app and then moving them to SSD causes stutter too. Copying on PC keeps the files intact so it’s not a hardware problem.
Here is an example

Drohne

Folder

1drv.ms

The SD files are the original and fine files from the drone
The kopiert are the copies.

Can someone please help

 

[sparksd]

I bought MAVIC AIR 2 and for the same reason I bought SSD. But I noticed issue in copying videos from iPad Pro to SSD - corrupted video files or video files dropping frames. I thought it's something wrong with SSD, so I returned the SSD.

Then I bought external WD HDD, but it was not recognized by iPad or MAC because it's NTFS...

Then I followed guidance to reformat to exFAT in a PC, then it won't be recognized still by iPad or MAC

Today I tried to reformat this HDD to "Mac OS Extended" format using a Mac.

Problem solved!!!!!

But I can't access this HDD on a PC any more

So in summary, it's the compatibility issue between Files app and exFAT in my assessment

Agree. For external storage formatted exFAT, iPadOS support stinks.