GPG Error (Trusty 14.04)

Every time I try to run sudo apt-get update I get the following after Reading Package Lists:

W: GPG error: http://repos.codelite.org trusty InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 6856E1DB1AC82609.

I have been looking everywhere and have found an identical problem here, but this solution did not work for me.

It looks like you need to fetch the CodeLite developer key.

Try adding the key manually with

sudo apt-key adv --fetch-keys http://repos.codelite.org/CodeLite.asc

After you do this, go ahead and try reinstalling the package you were installing.

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