My anti-virus accidentally deleted the folder to access my photos frm my sony a330..how can i access my photos now or retrieve the folder? every time i created a new folder or open it, it says empty.

It's not necessarily your anti-virus. Did you format your memory card in your camera when you first got it (as Sony recommends)? If not, the card will work temporarily, but the file structure will inevitably corrupt as pictures are added and deleted. Recommend first trying to download your photos using a USB card reader. If that doesn't work, your next step would be to try recovery software with the card reader and memory card. Here's a YouTube video of your freeware options, and here's more info on how to use them, and where to get them. After you've recovered your photos to your computer, format the card in your camera using the camera's format feature in its menus.