A MicroSD card is a tiny, ultra-portable media storage device encased in plastic about the size of a fingernail and popularly used as portable storage for cell phones. Depending on its storage capacity, a MicroSD card can hold hundreds, even thousands, of photos, videos, music files, documents and more. Many users password-protect the entire card through their phone's interface in order to restrict other users from obtaining access to its files. Without this password, no one can open any other files on the card while it is in the phone. A lost password doesn't have to mean the permanent loss of data, however; there is a simple workaround in Windows that, with some effort and patience, will reveal the password on the card.
Insert the MicroSD card into an available media reader slot on your PC. If your media reader can't read MicroSD cards, but can read ordinary SD cards, first insert the MicroSD card into an SD adaptor, and then insert the adaptor into the slot. You will see an autoplay menu for the disk pop up on the screen.
Open the folders on the disk and navigate to the "System" folder. Click on the "Open folders to view files" option from the autoplay menu, then double-click on the folder that says "System." This is where your card's password file is stored.
Open the password file. In the "System" folder, find the file that has MMCSTORE somewhere in its name. It may have additional letters, numbers and characters, but it will always have MMCSTORE in the title. Double-click on this file to open it in Notepad. The text inside this file is your lost MicroSD password.
All major operating systems will display some kind of autoplay menu upon insertion of an SD card into the media reader slot. The menu will vary slightly depending on the operating system, but both Mac and Linux will give you similar options with the above instructions.
Do not select any option that suggests it will reformat or restore your disk. This will likely wipe out all the data on your disk, and you'll have to use a data recovery software to get it back.