tkinter and scrabble solver problems

Although I removed the scrollbar ( I guess you will figure out how to add that too) I completely rewrote your code, to be more pythonic, and easier to read and write. However I tried to stick to your code as much as possible.

I guess it is working now:

Here is the dictionary.dat I used:

beastlemonapeappleseapeaorangebat

And here is the code itself:

# Import python modulesimport tkinterimport tkinter.messageboxfrom collections import Counter# Module level constantsSCORES = {'A': 1, 'C': 3, 'B': 3, 'E': 1, 'D': 2, 'G': 2, 'F': 4, 'I': 1,          'H': 4, 'K': 5, 'J': 8, 'M': 3, 'L': 1, 'O': 1, 'N': 1, 'Q': 10,          'P': 3, 'S': 1, 'R': 1, 'U': 1, 'T': 1, 'W': 4,  'V': 4, 'Y': 4,          'X': 8, 'Z': 10}class App(tkinter.Tk):    def __init__(self, word_list, *args, **kwargs):        # Initialize parent class by passing instance as first argument        tkinter.Tk.__init__(self, *args, **kwargs)        # Store values        self.word_list = word_list        # Setup main window        self.title('Scrabble Solver')        # Create widgets        rack_label = tkinter.Label(self, text='Enter your rack')        self.rack_entry = tkinter.Entry(self)        rack_button = tkinter.Button(self, text='Enter', command=self.search)        quit_button = tkinter.Button(self, text='Quit', command=self.quit)        self.valid_list = tkinter.Listbox(self, width=40, font='Courier')        # Place widgets        rack_label.grid(row=0, column=0, sticky=tkinter.W)        self.rack_entry.grid(row=1, column=0, sticky=tkinter.W)        rack_button.grid(row=1, column=1, sticky=tkinter.W)        quit_button.grid(row=1, column=2, sticky=tkinter.W)        self.valid_list.grid(row=2, columnspan=3, sticky=tkinter.W)    def run(self):        # Enter event loop        self.mainloop()    def error(self):        # Throw and error message dialog        tkinter.messagebox.showinfo('You have entered too many letters!')    def search(self):        # Cleanup up valid list        self.valid_list.delete(0, tkinter.END)        # Get data of entry, and make them lower case        rack = self.rack_entry.get().lower()        # Check length of data        if len(rack) <= 8:            return self.find_valid_words(rack)        self.error()    def find_valid_words(self, rack):        # Create a dictionary for valid words and its values        valid = {}        rack_chars = Counter(rack)        for word in self.word_list:            word_chars = Counter(word)            if word_chars == word_chars & rack_chars:                valid[word] = sum(SCORES[letter.upper()] for letter in word)        # Sort the results and insert them into the list box        if valid:            for word, score in sorted(valid.items(), key=lambda v: v[1], reverse=True):                self.valid_list.insert(tkinter.END, '{:<10} {}'.format(word, score))        else:            self.valid_list.insert(tkinter.END, 'No results found.')if __name__ == '__main__':    # Open dictionary file and scan for words    with open('dictionary.dat', 'r') as f:        all_words = [word for word in f.read().split()]    # Create instance and call run method    App(all_words).run()