Plaintext with 'T' and 'E' alphabets missing and encrypted with Vigenere Cipher I wrote the normal code to decrypt a Vigenere cipher encrypted text without knowing the key. But that won't work for this are two of the alphabets are missing and that would mess up the frequency analysis. Any idea on how to go about decrypting it?
frequency analysis works just fine even without a few common letters. In fact you don't even need to know the frequency in the underlying alphabet it is sufficient that it is far from uniform. You can rotate the columns so as to make the frequencies in each match.
Alternatively using an English bi-gram frequency table you can break this quickly even without two letters.

Do you know if the letters were removed from plain text in preprocessing or is this a clever text without these? it makes no difference for first method but some if you bring in external frequency tables.