Evolution with GnuPG: "no imported public key" even if it is imported

I was running Evolution on Debian buster (testing) amd64 with GnuPG to encrypt mails. I have my GPG private key on a YubiKey actings as GPG smartcard. As Evolution somehow failed to load my calendars using CalDAV, I [resetted Evolution](https://askubuntu.com/a/243220/) . CalDAV is working fine now. But after the reset another issue appeared: GPG encrypting/signing isn't working anymore. Mails are decrypted without problems. Furthermore, I can not choose my own GPG key in the account's settings, even if it is imported properly and gets listed in gpg -K: I'm now able to choose my key. When I try to send an encryoted mail this fails with Evolution showing the following error: Could not create message. You may need to select different mail options. Detailed error: Failed to encrypt: Invalid recipient specified. A common issue is that the gpg2 doesn’t have imported public key for this recipient. But my public key **is** imported. The same thing happens when I disable the option Always encrypt to myself when sending encrypted messages with this account. The error then is: Detailed error: Failed to encrypt: Invalid recipient specified. A common issue is that the gpg2 doesn’t have imported public key for this recipient. Encrypting/signing from command line with the gpg command works fine. Using a private key which is not on a smartcard also did not work. Resetting both GPG and Evolution did not work. I don't have any idea now what I should do now. Thank you all in advance :) **EDIT**: output of strace -p $(pidof evolution) -f -e trace=execve when decrypting (works fine): [pid 4613] execve("/usr/local/bin/gpg2", ["gpg2", "--verbose", "--no-secmem-warning", "--no-greeting", "--no-tty", "--status-fd=66", "--command-fd=67", "--verify-options", "show-photos", "--photo-viewer", "/usr/lib/evolution/camel-gpg-pho"..., "--decrypt", "--output", "-"], [/* 34 vars */]) = -1 ENOENT (No such file or directory) [pid 4613] execve("/usr/bin/gpg2", ["gpg2", "--verbose", "--no-secmem-warning", "--no-greeting", "--no-tty", "--status-fd=66", "--command-fd=67", "--verify-options", "show-photos", "--photo-viewer", "/usr/lib/evolution/camel-gpg-pho"..., "--decrypt", "--output", "-"], [/* 34 vars */]) = 0 When encrypting (which fails): [pid 4537] execve("/usr/local/bin/gpg2", ["gpg2", "--verbose", "--no-secmem-warning", "--no-greeting", "--no-tty", "--batch", "--yes", "--status-fd=67", "--encrypt", "--armor", "-u", "my@mail.address", "-r", "", "--output", "-"], [/* 34 vars */]) = -1 ENOENT (No such file or directory) [pid 4537] execve("/usr/bin/gpg2", ["gpg2", "--verbose", "--no-secmem-warning", "--no-greeting", "--no-tty", "--batch", "--yes", "--status-fd=67", "--encrypt", "--armor", "-u", "my@mail.address", "-r", "", "--output", "-"], [/* 34 vars */]) = 0 The file /usr/local/bin/gpg2 doesn't exist and seems not to be [part of any Debian package](https://packages.debian.org/search?suite=buster&arch=any&mode=exactfilename&searchon=contents&keywords=%2Fusr%2Flocal%2Fbin%2Fgpg2) . **EDIT2**: The command @Hauke Laging posted in the comments works, but I interactively needed to confirm to execute the action (as it also was when I manually encrypted using the command line): echo foo | /usr/bin/gpg2 --status-fd=1 --encrypt --armor -u my@mail.address -r recipients@mail.address --output - While the command which Evolution wants to execute fails (I removed the `` as that causes issues with zsh): ➜ ~ gpg2 --verbose --no-secmem-warning --no-greeting --no-tty --batch --yes --status-fd=67 --encrypt --armor -u my@mail.address -r recipients@mail.address --output gpg: Fatal: status-fd is invalid: Bad file descriptor Setting --status-fd=1 still fails, but with different errors: ➜ ~ echo "foo" | gpg2 --verbose --no-secmem-warning --no-greeting --no-tty --batch --yes --status-fd=1 --encrypt --armor -u my@mail.address -r recipients@mail.address --output - [GNUPG:] KEY_CONSIDERED 0 gpg: using pgp trust model gpg: using subkey instead of primary key [GNUPG:] KEY_CONSIDERED 0 gpg: automatically retrieved 'recipients@mail.address' via Local gpg: : There is no assurance this key belongs to the named user [GNUPG:] INV_RECP 10 recipients@mail.address [GNUPG:] FAILURE encrypt 53 gpg: [stdin]: encryption failed: Unusable public key **EDIT3:** Just tested: signing messages from Evolution works as well as decrypting. When I manually encrypt a message using the command line, I get the following message which I think causes this issue: ➜ ~ echo "foo" | gpg --encrypt -r recipients@mail.address --armor gpg: automatically retrieved 'recipients@mail.address' via Local gpg: : There is no assurance this key belongs to the named user sub rsa4096/ 2015-10-14 Recipient's Name Primary key fingerprint: Subkey fingerprint: It is NOT certain that the key belongs to the person named in the user ID. If you *really* know what you are doing, you may answer the next question with yes. Use this key anyway? (y/N) y -----BEGIN PGP MESSAGE----- [...] -----END PGP MESSAGE----- **EDIT4**: As the message above is caused by missing ownertrust (at least I think so), I'd like to set the recipient's ownertrust using gpg --edit-key (which was not set before): gpg> trust pub rsa4096/ created: expires: usage: SCA trust: unknown validity: unknown sub rsa4096/ created: expires: usage: E [ unknown] (1). Pecipient's Name Please decide how far you trust this user to correctly verify other users' keys (by looking at passports, checking fingerprints from different sources, etc.) 1 = I don't know or won't say 2 = I do NOT trust 3 = I trust marginally 4 = I trust fully 5 = I trust ultimately m = back to the main menu Your decision? 3 pub rsa4096/ created: expires: usage: SCA trust: marginal validity: unknown sub rsa4096/ created: expires: usage: E [ unknown] (1). Pecipient's Name So I set the recipient's ownertrust, but why is there still this [ unknown] at the end?