Which folder you've used to do this
You need to to this in %APPDATA%\Litecoin folder:

Go to Start -> Run (or press WinKey+R) and run this:


Litecoin's data folder will open. For most users, these are the following locations:

C:\Documents and Settings\\Application data\Litecoin (XP)

C:\Users\\Appdata\Roaming\Litecoin (Vista and 7)

Note that "AppData" and "Application data" are hidden by default. Unhide from: Control Panel -> Folder Options -> View -> Hidden files and folders -> Show hidden files, folders or drives -> OK

Beware to NOT delete wallet.dat. You'll simply lose your coins.

Finally, an advice from me: I usually dig Google heavily, before giving up and asking questions. Google is man's best friend, the dog is the second best only