I dunno how, but I got back my previous deleted messages on the memory card.
Yesterday, I curiously see that there 2 different mail folder, one is in C drive and the other is in D drive. So, I remembered that my previous messages in the memory card was much more than in the phone memory. And I saw that the mail folder in C drive was bigger in size than in the E drive.
So, I try to copy all the mail folder in C drive and overwrite it in E drive.
When I open the messages in the memory card, I got back those which was overwritten before.
So, I just get confuse here. Why did I get back my overwritten messages after I copy the mail folder in C:\System\Mail and paste it in E:\System\Mail?
Were my messages in the memory card in the C drive, not in E drive as you said before?
May be you could make a conclusion about this, in case it happens to anyone else or to me for once again.
But God does exist and gave me a miracle, hehehe...