Assistance Cracking Classical Cipher Below is the cipher text I am trying to break and as you can see its rather short which is why I am having so much trouble.

WOYFN ZCMSH VUVTG BFUTW ABTZP FHIMF TFOSU UXFQC HKVKG MPUUQ 
MHRXI OVBRZ EPJYF KKVJW GEIOV HUKEB JUNSM THIMF TFKUB ULMMQX


What I know about this ciphertext:


Key is 6 characters long and repeats (Given by the person who encrypted it)
There is a single character missing from the start of the ciphertext! (Also given)
It uses a simple cipher I believe a vigenere cipher.
Friedman IC: 1.143 (kappa-plaintext: 0.4396) which is why i think its a vigenere cipher


I have spent many hours on this but to be honest im not very good at breaking these codes.

My problem that iv run into is that once I break the cipher into its sections they are all very short and hence frequency alaysis fails.

I would really appreciate if someone could either confirm or find the crypto system being used as well as any more information about how one would find the plaintext + key or better yet find the key itself and explain how you manage it with such a short piece of ciphertext

Edit: There was some debate as to the validity of this question so here is some more information from my attempts:

Streams:


?ZUUZFUKUXZKEKSFU IC = 3.6833 (kappa-plaintext: 1.4167)
WCVTPTXVUIEKIEMTL IC = 1.1471 (kappa-plaintext: 0.4412)
OMTWFFFKQOPVOBTFM IC = 2.1029 (kappa-plaintext: 0.8088)
YSGAHOQGMVJJVJHKM IC = 1.3382 (kappa-plaintext: 0.5147)
FHBBISCMHBYWHUIUQ IC = 1.5294 (kappa-plaintext: 0.5882)
NVFTMUHPRRFGUNMBX IC = 0.9559 (kappa-plaintext: 0.3676)


These numbers don't look good. they are almost all drastically off normal distribution for any language. 

The main point to my question is:


Does Vigenere Seem like a reasonable fit (given those streams are correct)?
Is it possible to use that analysis in any way? I cant see how it can be effective with only 17 characters per stream. Most letters frequencies are 0.
What other ciphers are possible? How could I identify that they are in use? 


I am happy to provide more information I am just not sure what else is useful.
I don't know the solution, but since you say you're only asking for hints, here's a few that occurred to me:


If this is a Vigenère cipher, the missing character at the beginning should not matter (much): if you encrypt a message with the key FOOBAR and drop the first letter of the output, you can decrypt the resulting ciphertext with the key OOBARF.
As ewanm89 notes, the obvious way to attack a Vigenère cipher, after you've determined the key length is $n$, is to write it with $n$ letters per row and attack each column as if it were a Caesar cipher.  There are automated tools for doing that, such as pygenere; they may not always give the correct answer for very short messages, but yours looks long enough that they should at least have a decent chance.
The most notable feature I see in your ciphertext is that the string HIMFTF occurs twice, at offsets 26 and 86.  That does strongly suggest that the key length may be a divisor of 60; alas, 60 has lots of small divisors (including 6, which you believe the key length to be), so that doesn't really give that much information.  It does at least rule out 7, 8 and 9 as likely key lengths.