SD cards often mount read-only on Windows despite being unlocked and always working in cameras

I have a HP netbook that's at least three years old and running Windows 7 Starter. It has a built-in SDHC card slot.

I have a couple of 8 gig SDHC cards that I switch between my digital camera and the netbook. They're full-sized cards like the computer slot is. Not MiniSD or MicroSD. They are from different manufacturers and were bought at different times, but each is now a few years old.

I've gone through half a dozen point-and-click cameras and none of them have ever complained that the SD card is write protected. I never set the write-protect tabs to "locked".

Yet increasingly when I insert the SD card into the computer it will mount as read-only. It used to happen once in a while but now it happens about two times out of three.

The only workaround I have found so far is to eject the SD card and reinsert it. This works about half the time.

Is this a known bug in Windows or in certain HP netbooks? Is there a known fix? If not is there a more reliable workaround?

Solution 1:

I've often seen the read-only problem arise from not properly unmounting/ejecting a USB drive/card before removing it, leading to a corrupted filesystem that only wants to mount as read-only until it's chkdsk'd or fsck'd.

Always unmounting / "Safely Remove"-ing devices and even waiting an extra few seconds seems to greatly lessen the problem occuring. Also when I formatted the drives to something other than FAT32, like NTFS or ext3, something with a journal, it seemed to help immensely too, then even if an error occurs it's very minor, no files or filenames are lost, while FAT32 could loose ALL the filenames + some files.

Cards & USB drives do also sometimes start to be "read-only" when they start to fail... or the card reader or USB cable/HUB/port starts to fail...