Hello, Im new to Kali and Linux and I may be doing something incorrectly. I recently tried to verify an ISO. I downloaded the file from http://cdimage.kali.org/current/ I downloaded kali-linux-2017.3-amd64.iso. The sha256sum hash matched correctly with the file. However, the signature DID NOT validate. The message I got was: WARNING This key is not certified with a trusted signature, there is no indication that the signature belongs to the owner. When I imported the Public key with the command: gpg --keyserver hkp://keys.gnupg.net --recv-key 7D8D0BF6 I got an error saying 127 signatures not checked due to missing keys. Here is the Public key that I have on file:

-----BEGIN PGP PUBLIC KEY BLOCK-----
Version: GnuPG v1

mQINBE9U1CgBEAChen9+cvBS8ioHoCU6wBbL9jaIk5P7ZkPpjD sovMvimqZaozS8
fEAZM23gJlFratc+rRllV9hPZmGqhtT50RLDzC3yFOvFnJqAPv pVDO2ipQCVnJDX
0eWDhT62RDwk+FhjksEDwP7Yc4CgohdGDYQu1zTBSLL5qen3rc kCnHF2OnSiKnYM
8YCIKAYMt4VRArAvivjOMspN+1xy2S8GYXX2felsu3Ir1DXvUI E7b/9sdK6MzBcq
joDH34OqX6isqAW0+K93lmVN+U4yFMzfEB74UMQNWKg39mCB0K/VfQ89ih4zvF9a
zENbFzfF0O0h09oHF4ZTaUFeI8JImp/x9FC+LveUyJot9t/xv0HVUd08Y4PgO48C
iXOTqqqm/DPF0AbHJGpTuonOsKy3/dYhk7Fvsfn02DMds+RKsukBEzypTIIIzMBF
Uwiq/GaaNRWw6lnOyE4wMmpwRa11QVDDWkMpuOr1tPV7M+EMAhZY7cy HDmRTOFL3
H0CxYnInis+k1NQikqtLxNrzWdxsXU25BMbEsAQq7aRTs7wpOn UK+yY+qTG/V5nl
J6II+/CtWJthIef22r8EYX1BQOXRggamy0nxViC3S6kjuU2Lb1qnDb/c7T9hB723
4T9yrRHJbygTvQD8BJBADgRy7+XInCp01V4nAJZSu20qopEg08 2SdWK9FwARAQAB
tCZLYWxpIExpbnV4IFJlcG9zaXRvcnkgPGRldmVsQGthbGkub3 JnPokCPgQTAQIA
KAIbAwYLCQgHAwIGFQgCCQoLBBYCAwECHgECF4AFAlTQ4K8FCQ sfpvgACgkQ7URP
8H2NC/a+XxAAm2WddciNyyEqNvM6TFo+/H/3UnCAbDGk+n5o4C8oOZ5pikqGy9MZ
wxnvXNRhtGc3xvFzQfzbG4qi2rHctu24Z+lCKpYsXiF7+LPb1w tVAn2kEuceVN9a
uWD5dCve1No1qiQN9Azk7R5Bw27ybtRLzEAuG2Va1dBp4YR61G IPOTGKJYOZ2nEJ
EInUkUprUn25yeBVNh1dWt/xfkZkgRnICY2yTyP4ffYbM/eFkkkGZG6RXaJ8v+AX
OcTrowxJfLymKea7OmyMPtugNaE4CG0gq6/po9XnqwK43jotx3l4M6Do3FZbjkWC
YpWSWnlJW69koEsLGt57doNF2R5HBrl8sgdE8g7R5ZIx4dZ3Sq R2SM0uA+k+V1zA
drgHnaBiYmXI9T+j6vTA+9R9wbYojkUkVwrLgUr25JrGTApfSx 8A9dSkHOTwFitv
IFEUs2Jpxvkqj+p5RNzbSOSAwTH8/pXSIa3a/sEzBR9oTGT9qSD8y587OPPJtzI6
DvGzWb0LAp6DDcooULbo+PeNmPP6Zh54uDChPhAichEwO/OUSdVGHdMabV9CBfHW
5gb15msz3T3a0MTnxDuIRJAgS0KYpZFQTqJAeG+ANh2L8QlXgj gkHFeho6TQshRh
tH9ig9g4lD90X853rRIoHiMiCox8aO/5EVjcDnnFy5y0h0de4xOa1Zm5Ag0ET1TU
KAEQAKDDgresg54DVGsGhS6hc85ENlA7dS8ljDOakbrGJlVuw2 zKkYJfNegIVt6h
l5aRE9kAyvwu56fJIsJMdtnFpCtlu3vO+2yhl9Yx9JPIyGVsRN eaQQgZE5Ps2+np
Qtut6osN+o8QJRJ8HeHj9DgGOksQ/cYuR3ye81zvtoReG1YKH0RjZq+SAPUjy9Mk
SaPnTZt0ofjIXTTKbyaTnZND1qqtWT/SwtVwmDbY5SJrHproC5aCiK3acAHByel6
ociOSLo37ZlHzeoS99zAJd+ALsv+BJVBVPQ471iO5bvkez/I3Q0AdwtdP3qW5kbu
76rUTVDH+6vjBEWUAj6p++ajvD+Mxhh3Q4VUUIwJXn8elC74UZ S3wpI60q6ZxxRn
GC8z10LsboUi72cgpyaxtV5oCweUgBT8SCtaAcnamTmD7DximU rzB6QT7/ckdrTO
sgYwcwVd/8EAmhw/WKd7GQ/UcUlrQL5N3s0Y0KJ/NVuEtCenVGS9pqIO4Fsw4/b+
NnCFfPdHs0tO+3aXi9n0mTlK93zKzNWT3ySrnvEq75VVVdcMkg OlcQbLO9YlmTRB
wuYA/4HgvOtxWjsVyhWV1sQ/jHjP4a1Hn5o+u30OK4804ChUbYr5kis4IANxXjnl
AoNIGnRvbBh/4H8U6AOtU/8cRFhMrsCYjtklUv4gY0J33IwzABEBAAGJAiUEGAEC
AA8CGwwFAlTQ4NYFCQsfpykACgkQ7URP8H2NC/Z+aw/+Ob/Rima3+oL5NnhiCuIG
TBy7+THcgdclEFKFY4lJGebLMKXDeKINLE1ZpChT9rd/Y9EQ0xgrKN8nGlc2B3mT
VrPijhdN2Tr+JMyNyx+wFKz36YSP/ZzOgz11Y0MANe4omgwTFMg+98e4W8yuTHOV
vYcW9JoquRJvU7CestmwyZmzxcbeLLlMQaa6squbdKiQJj55UJ da37/61pYd97LY
bBCbg4f7/rJUKnrMvoo53yyg3F3GB9tbs8MgYogWF5XYKZGlgou1ATL7bRO lnnDN
LtZsB9rRW0gLD/3ozGzJs5GWf5o5Us+mFpMCjfjgTf5Es8j28up3UI4kkUIO/Xzk
PEY5RAuAxmYX9cKqp9tR+RgbJAgpm4kJmjAq3oqgeqCmVy2WlU yCLnKwiS95buTq
nV5j8ffVhpxUDWIHSsqtzGvdjfWIipY5f4R9fOdGFFtLyG+H7X 9MTfGuRRwr3Bzj
UUM+oZdef813p2Zo4p7c1C/7DsKQs3ORbQlnlGtBDIfyZrDUnjTD2h9fnSjYgSut
56LWkLuhPRm+jZ+hqbJv4cUG5nyYZZqzVQdXypj5CAt2CCG10S qHTUEiWOKqZkMd
tGsD/AJGFuayuUJgSmeOUoJkI1uG9+t68dLGLUFm0Odj3BhqeDFOSDr EeHNZZ4//
N8VraGp82D32tiqQmWS5r+8=
=E6FO
-----END PGP PUBLIC KEY BLOCK-----

Please let me know if im doing something wrong. I was having issues with an prior installation, and the file size of the ISO image kept getting bigger that was saved on my usb stick which was wierd so I formatted everything and now im stuck here. Thanks in advance!