File changed into .exe & Folder hid due to USB virus

Hello,
I'm on a bad problem, when I took data from memory card, then that partition of the folder's properties changed into .exe & some other into .dll . That part is not open any folder(open as like 'dos') the folder size 24 KB is visible. Partition size while ago looks like,after restart my pc then all folders hid to the another partition of the disk.What I will be able to find my data again ? Please help me,I'll be your forever grateful.thanks.specify all possibility about recover my data.thanks again.
Entrance of any kind of virus has not been identified by the several type of anti-virus program me. Earlier on I had help from another place he failed to help me.i used Hyjackthis programme,malwarebytes-anti-malware, fseasyclean virus removal tool. but The problem remains as before.
I have some curiosity. (1) how the hidden folder can be expressed? (2) What dos can burn data to help? If so, how?
We will wait for your answer. thank you
your faithfully
vikas mehta

 

Can you boot into safe mode (F8) and restore the computer to an earlier time?