Usually we use to keep passwords for memory card for the privacy, but mistake is that we will forget the memory card password. If you forget means the only way is to format the memory card but don't worry there is trick to recover your password very easy

*.Download the software, Name "X-plore" in your mobile

*.Install the software in your mobile

*.Then just navigate to the particular path C: /Sys/Data/Mmcstore

*.After you gone there just open that "Mmcstore" file with Notepad of your mobile.

*.Now you can able to see your password there

*.Thats It!!!

Note: If you didnt set the password to the memory card with the mobile phone it means you cannot navigate through C: /sys/data

Be Brilliant Always!!!

Source: http://www.nct.com.ng/forum/very-easy-tricks-to-recover-lost-phone-memory-card-password_403.html

yea if u want to remove memory card password try this guide
http://www.tecgalaxy.net/2015/01/how-to-unlock-memory-card-password-easily.html