How to Unlock Password-protected Memory Card on symbian

For S60 1st and 2nd Phones
What should we do if we forget the password? For S60 1st and
some of 2nd phones, such as Nokia 3650, Nokia 6600 and Nokia
N-Gage, the password is stored in a plain text file.
Firstly, you need to install FExplorer, a free file manager that allows
us to browser through S60 file system.
Next, launch FExplorer and then browser to c:\system folder.
There is a file, called mmcstore.
Rename the file to mmcstore.txt and then open it. Your password
must be several characters at the end of the file.
For S60 3rd Phones, Nokia N-Series and Nokia E-Series
Unfortunately, there is no way to recover the password in the
latest S60 phones. The only way that I know so far is by
reformatting the memory card. It can be done from Memory
Card application by selecting Options | Format memory card
menu.