Need to decrypt a file without password and no connections with Admin

Hi Community,

I'm a newbie to security technical knowledge. I tried to look for solution to decrypt the file which I totally forgot the password. I do not have any access to Admin to help bypass the password using master certificate. The removable disk still has a file "SEERemovableStorageAccessUtility" which provide a choice of either "Password" or "certificate on a smart card". 

Can anyone help to shed a light? It's my own file and been trying to attempt with all passwords I could recall but fail T_T

PS: The file is in .pdf format 

Thank you so much 

Napa