The .listdir() method gives you filenames without paths only, you are probably trying to open a file in the current directory, not in the directory named by path.

You have to use the os.path.join function to put path and item together:

for item in added:
    print item
    fullfilename = os.path.join(path, item)
    ad=open(fullfilename,'r')
    print ad.read()