I updated my phone software and when I inserted the memory card back into cell it was locked. I have forgotten the password and can't access it. I've used the FExplorer but I can't find the file called mmcstore. Can anyone help please?

Try going to the store you got your phone... since they will know the phone is actually yours they will be able to help. They will have tools and utilities not available to the general public. I'm sure you won't be the first person that has had this happen.