So you mean to say you set a password on your memory card and forgot the password to unlock and get access to it.right? If yes ,then you can refer to link below from Faq section of kioskea for instructions how to remove the password :
I have Nokia 3110c mobile.And I lost the password of the memory card .When I tried to delete the password, it asks the current password (but I don't know!).You have suggested to open "file manger".It is not there an my mobile
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