我可以通过这种方式重现错误：

% python
Python 2.7.2+ (default, Oct  4 2011, 20:03:08) 
[GCC 4.6.1] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> 'k\xf8**e' in [u'k\xf8**e']
__main__:1: UnicodeWarning: Unicode equal comparison failed to convert both arguments to Unicode - interpreting them as being unequal
False

因此，也许s是str object和liste或ordliste包含unicode，或者（如eryksun在评论中指出的）反之亦然。解决方案是解码str objects（最有可能使用utf-8编解码器）以使其成为unicode。

如果这样做没有帮助，请打印并发布输出

print(repr(s))
print(repr(liste))
print(repr(ordliste))

我相信可以通过将所有字符串转换为来避免该问题unicode。

1. ordliste从中生成时norsk.txt，请使用 codecs.open('norsk.txt','r','utf-8')：

   encoding = sys.stdin.encoding
   

   with codecs.open(‘norsk.txt’,’r’,’utf-8’) as fil:
   ordliste = [line.rstrip(u’\n’) for line in fil]
   

2. 尽快将所有用户输入转换为unicode：

   def get_unicode(widget):
   streng = widget.get()
   try:
       streng = streng.decode('utf-8')
   except UnicodeEncodeError:
       pass
   return streng
   

所以也许试试这个：

import Tkinter as tk
import tkMessageBox
import codecs
import itertools
import sys

alfabetet = (u"abcdefghijklmnopqrstuvwxyz"
             u"\N{LATIN SMALL LETTER AE}"
             u"\N{LATIN SMALL LETTER O WITH STROKE}"
             u"\N{LATIN SMALL LETTER A WITH RING ABOVE}")

encoding = sys.stdin.encoding
with codecs.open('norsk.txt','r',encoding) as fil:
    ordliste = set(line.rstrip(u'\n') for line in fil)

def get_unicode(widget):
    streng = widget.get()
    if isinstance(streng,str):
        streng = streng.decode('latin-1')
    return streng

def siord():
    alfa=lagtabell()
    try:
        streng = get_unicode(ordinn)
        ordene=finnord(streng,alfa)
        if len(ordene) == 0:
            # There are no words that match
            tkMessageBox.showinfo('Dessverre..','Det er ingen ord som passer...')
        else:
            # Done: The words that fit the pattern
            tkMessageBox.showinfo('Ferdig',
                'Ordene som passer er:\n'+ordene.encode('utf-8'))
    except Exception as err:
        # There has been a mistake .. Check your word
        print(repr(err))
        tkMessageBox.showerror('ERROR','Det har skjedd en feil.. Sjekk ordet ditt.')

def finnord(streng,alfa): 
    liste = set()
    for substitution in itertools.permutations(alfa,streng.count(u'*')):
        s = streng
        for ch in substitution:
            s = s.replace(u'*',ch,1)
        if s in ordliste:
            liste.add(s)
    liste = [streng]+list(liste)
    return u','.join(liste)+u'.'

def lagtabell():
    tinbox = get_unicode(bokstinn)
    if not tinbox.isalpha():
        alfa = alfabetet
    else:
        alfa = tinbox.lower()
    return alfa

root = tk.Tk()
root.title('FeudHjelper av Martin Skow Røed')
root.geometry('400x250+450+200')
# root.iconbitmap('data/ikon.ico')

skrift1 = tk.Label(root,
                text = '''\
Velkommen til FeudHjelper. Skriv inn de bokstavene du har, og erstatt ukjente med *.
F. eks: sl**ge
Det er kun lov til å bruke tre stjerner, altså tre ukjente bokstaver.''',
                font = ('Verdana',8), wraplength=350)
skrift1.pack(pady = 5)

ordinn = tk.StringVar(None)
tekstboks = tk.Entry(root, textvariable = ordinn)
tekstboks.pack(pady = 5)

# What letters do you have? Eg "ahneki". Leave blank here if you want all the words.
skrift2 = tk.Label(root, text = '''Hvilke bokstaver har du? F. eks "ahneki". La det være blankt her hvis du vil ha alle ordene.''',
                font = ('Verdana',8), wraplength=350)
skrift2.pack(pady = 10)

bokstinn = tk.StringVar(None)
tekstboks2 = tk.Entry(root, textvariable = bokstinn)
tekstboks2.pack()

knapp = tk.Button(text = 'Finn ord!', command = siord)
knapp.pack(pady = 10)
root.mainloop()