Cannot Decrypt ASC attachment or Import Key

[Xy Logan]

Hello,
I’m trying to import a key sent to me as an attachment, as asc file, but in Thunderbird/Enigmail the asc attachment’s “Import OpenPGP Key” option is greyed. I’ve imported a key successfully before, but not an encrypted one. None of my attempts to decrypt it so far will work. (Apologies, this is close to other posts I have read here, but not the same, and I can’t find my issue addressed anywhere online. I’m aware that it may be a stupid beginner mistake.)
I’m running Windows 10 / Enigmail version 1.9.6.1 / GnuPG 2.1.19

Here is what happens when I try the options I do have access to in Tb/Enigmail:

1) Decrypt and save - prompts enter my private key password - I enter password, but this error box comes up:
Enigmail Alert:
Error - decryption failed
gpg: decrypt_message failed: Unexpected error

2) Decrypt and open - same thing happens

3) If I try to just save the asc file and then import it via Enigmail Key Management, no error message comes up, the Key Management screen simply does not change (it goes blank for a second after I click to import the key and then appears just as it was).

4) If I try to just open the asc file in Notepad, it just shows a bunch of encrypted characters.

Thanks, I really appreciate any help.

[Ludwig Hügelschäfer]

I'm afraid, you need to save the encrypted key and decrypt it using the GnuPG command line application:

gpg2 --decrypt "File.asc" -o "DecryptedFile.asc"

Then import the decrypted key using Enigmails Keymanager: File -> Import keys from file.