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Can't Format USB Drives

dintymoore

dintymoore

macrumors member
Original poster
Jun 27, 2008
36
3
A few years ago I bought two 32GB USB flash drives, one Belkin and the other a SanDisk. Recently they both have gone into "Read Only" mode. I've backed them up and would like to reformat them in Mac Extended format, they are currently formatted in MS DOS (FAT32) format. In Disk Utility the choices are greyed out. In the Get Info window under "Sharing & Permissions" it says "You can only read".
The drives act this way on my MacBook running 10.6.8 and a Mini running Yosemite.
I found some info online but am not familiar with Terminal. Disk Utility in Safe Mode didn't yield results.
Does anybody know the solution to this?
 
In the left hand column of disk utility are you clicking on the device icon or the volume icon? You may need to find and enable the “advanced” button. You should see a hierarchical list with the volume listed below the device. Click the device and see if you can format.
 
Sometimes when an old flashdrive (that was previously working) suddenly becomes "read only", it indicates that something has failed on the drive internally.

Usually, the best thing to do is ... copy the data from it and... toss it.
Just be happy that it chose not to "go completely dark" on you.

As a "last attempt", I would take the drive to a WINDOWS PC and try to erase them on that.
Try a couple of different formatting schemes (exfat, etc.).
If that doesn't work, look for the nearest trash can and toss 'em into it.
 
Longkeg I have tried both (see attached pics) in Leopard and Yosemite. I don't see any button to enable "advanced" options.

Fishrrman that's pretty much where I'm at. The drives do have important files on them so they are backups, but both are both good brands and only about 3 years old. I'm asking around to see if any of my friends have Windows computers, I suspect formatting them that way has a chance of working.

I found lots of webpages devoted to this and was able to get Terminal to try what someone suggested but that didn't work.

I'm guessing that when I bought the flashdrives they came formatted in MS-DOS (FAT32) and maybe if I had formatted them in Mac Extended then this wouldn't have happened. Since it happened to two flashdrives seemingly at the same time I suspect something in the continuing saga of idiotic operating software upgrades is what caused this.

Thanks for your replies.
 

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In the example where you have the San Disk device selected you have clicked on the “Erase” tab. What happens when you click on the “Partition” tab? I think you have your photos mislabeled. The “device” photo is showing the volume and “volume” is showing device.
 
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Longkeg said:
In the example where you have the San Disk device selected you have clicked on the “Erase” tab. What happens when you click on the “Partition” tab? I think you have your photos mislabeled. The “device” photo is showing the volume and “volume” is showing device.
Click to expand...

Oops, yes my photos are mislabeled... should be as you stated.

When I select "Partition" I still get greyed out options (see attached).
 

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I was unable to format the drives on a Windows computer and also on an old Mac running OS 9. Both computers wouldn't recognize one USB drive and said that the other was write protected.
 
Yup. I agree with Fishrrman. Your drives are probably toast. A final test would be to buy a new drive and reformat to Mac OS Extended right out of the box. If successful you’ll know the old drives are bad.
 
Yes, the drives are probably bad, or at least have corrupt files that have made them shut down to save what's already there.

As far as First Aid, when I use that on my Mac Mini running Yosemite the only option available is "verify disk", the other options for permissions and to repair the disk aren't even greyed out, they're just a black space.

About a week ago I bought a new 32GB San Disk USB drive and right out of the box formatted it to Mac Extended and we'll see how that goes... but the other ones lasted 3 or so years so my main concern is more:

These USB drives are to back up my artwork. Now I'm wondering if I'm using the right format. DVD's seem flakey as the surface is open to scratches like an old LP record. Now it seems that USB drives aren't all that safe. Or are they? I don't use any cloud/internet places to save anything, that seems real stupid to do, you're trusting people you don't know and will never meet. So maybe the best thing is just what I'm doing, save a bunch of USB drives and SD cards in multiple places.
 
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I have a couple of "real" hard drives that I use to back up files and installers.
I have been using flash drives for about 20(?) years now. I still have the first flash drive that I ever bought (64 MB). It still works, and has some old firmware for the original iMac G3, plus some other old stuff. When my 2nd ever flash drive started working VERY slow about 2 weeks after I bought it, I realized there must be be some natural limitations in that format. As those flash drives became cheaper and cheaper, I also could tell that flash drives are NOT for archiving. They are made for daily use, as working tools.Make sure that you back up your software tools to reliable media, such as external hard drives. Two different storage drives are minimum, and a RAID setup shouldn't be one of those backups.
 
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Thanks for the comments. DeltaMac I'm like you - still have the first USB drive I bought from the G3 days, a 64MB Lexmark which still works.
I get the feeling that my USB drives aren't really worn out, they just need to be wiped clean and San Disk doesn't want to waste time on messing with it, but I do see on the link chabig posted about getting a replacement.
I have lots and lots of backups, probably well over a dozen because I put my main artwork files on our computers and "real" hard drives, I didn't realize that USB drives are thought of as less permanent than other media, but makes sense since they keep getting messed with. In that way maybe DVD's that you rarely use (in a fire safe) are not so bad.
When I first started gigging with MIDI systems (early 80's) I made a lead box to hold the disks (and kryptonite) for a Commodore 64 we used because I didn't know if stuff like the driveshaft in the car and big speaker magnets would mess things up. Turns out they don't and people would put floppies on bass cabinets that had 10 lb magnets and it didn't do anything.
While I'm working on Photoshop, I'm always saving every 5-10 min to the MacBook's hard drive and then every 1/2 hour or so I copy those saves to an external Toshiba hard drive and the San Disk USB drive. I'm kinda paranoid about it but that way the worst I can loose is the last 1/2 hour.
 
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OP wrote:
"These USB drives are to back up my artwork."

I wouldn't depend on USB flash drives for much more than "short-term" storage.
They don't have the reliability of "regular" hard drives.

If you want to archive data that is REALLY important to you, I'd suggest you investigate the "M-Disc" format.
It looks like a regular optical DVD or BluRay disc, but uses a special non-dye layer that won't deteriorate over time as will dye-based optical discs.

You need a DVD/CD/Bluray burner that is "M-Disc capable" on which to burn them.
You also need the M-Disc media, of course.

But once burned, these are touted to have a lifetime of many many decades (into the hundreds of years) -- again because they do not use dyes to record data (instead, they use some kind of mineral-based layer on which the optical laser interacts).
 
Thanks for the info, I'd not heard about the M-disc format.

For now I think I will continue on with my "always carry 100 spare tires so you'll at least have 1" redundant approach, that's the way nature does everything.
 
dintymoore said:
Thanks for the info, I'd not heard about the M-disc format.

For now I think I will continue on with my "always carry 100 spare tires so you'll at least have 1" redundant approach, that's the way nature does everything.
Click to expand...

Hi, you have to use terminal to fully reformat a memory card
Also did your mate get his MacPro sorted that was only starting with the hair dryer method?

Cheers
 
Solution is easy, if it is a SanDisk microSD memory card that is housed in an adapter: Simply toggle the physical *lock* switch on the adapter.

It's unfortunate that this feature is not clearly highlighted in the SanDisk product literature or in Apple user forums. Many customers probably end up throwing away non-defective products. See the manufacturer's website:

kb.sandisk.com

Support for Western Digital Hard Drives | Western Digital

Find support for your internal or external HDDs. Read FAQs for self-service troubleshooting or submit a warranty claim. Register a product or check your order status; or download device software.
kb.sandisk.com kb.sandisk.com
 
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