[General Questions and Answers] chan.sk:
I would like to share my experience with you guys out there.

Just now, I had a situation where I lent a 32GB microSD with an adapter to a friend, and when he returned, the PC and my Android Tablet could not read the microSD. Normally, the microSD and adapter is recognised as drives G: for adapter and H: for microSD. I only got a G:, meaning the adapter is ok.

I checked it on my Android tablet - took out the 8GB microSD and inserted the 32GB microSD. Android tablet reported "Damaged microSD". When I connected the tablet as USB drive (USB Debugging is ON). PC still does not see the microSD. I got drives G: (for Android tablet) and H: (for microSD), but the PC cannot display the contents of H: although it displayed contents of G: (showing the filesystem of the Android tablet).

I removed the 32GB microSD out of the Android tablet and re-inserted the original 8GB microSD, and horrors of horrors, the Android tablet reported "Damaged microSD", and when I connected the tablet to PC as a USB drive, PC also cannot read the microSD.

I tried using Partition Magic and Minitool - both reported only the SATA hard-drive. No other drives.

I tried Windows Format - cannot recognise drive.

I tried SDFormatter V4.0 - microSD does not show up as a drive.

I read through all the posts in this thread and tried the "chkdsk /f /x <microSD drive>", using the adapter and microSD connected by USB to PC. I got "cannot open volume for direct access".

I thought both my microSDs were dead goners.

Then I remembered something from my Linux / Android experience - I need to UNMOUNT and MOUNT drives when removing or adding.

Success!

So, with the 8GB microSD in Android tablet, I went to Settings-Storage and did a UNMOUNT followed by MOUNT, and I could access the microSD with the Android File Explorer. So, I connected as USB drive to PC and now it shows drives G: (Android Tablet) and H: (microSD), and Windows File Explorer can also see the same drives and their contents.

I UNMOUNTED the 8GB microSD and removed it. I then inserted the 32GB microSD, did a MOUNT, and it showed up in the Android File Explorer. I connected as USB drive to PC and now it shows drives G: (Android Tablet) and H: (microSD), and Windows File Explorer can also see the same drives and their contents. I tried Windows Format, but it reported some errors and I could not carry out the format.

Next I verified with the software that, at first, failed to see the microSD.

With the 32GB microSD in the Android tablet:

Partition Magic and Minitool - both reported the SATA hard-drive and microSD.

Windows Format - can recognise drive.

SDFormatter V4.0 - microSD shows up as a drive.

Tried the "chkdsk /f /x <microSD drive>" and it went with no error messages.

After the ""chkdsk /f /x <microSD drive>", I tried to do a Windows Format and this time, it did not report any errors and successfully formatted it.

My conclusion drawn from this experience:

a. To remove a microSD from an Android device, you need to UNMOUNT. This is similar to the "Safely Remove Hardware" icon in the PC Windows system.

b. When a microSD is reported as a "Damaged SDcard" by Android, you can MOUNT storage card from Settings to try get it recognised.

Hope this helps to save some nerve-wrecking moments for those with similar encounters.