A record for problems after ubuntu upgrade

When run gnome-control-center, the errors throws:

gnome-control-center: symbol lookup error: /usr/lib/x86_64-linux-gnu/libwebkit2gtk-4.0.so.37: undefined symbol: gcry_mpi_ec_decode_point, version GCRYPT_1.6

and run sudo apt update,another error throws:

Get: 1 http://us.archive.ubuntu.com/ubuntu focal InRelease [265 kB]
Err http://us.archive.ubuntu.com/ubuntu focal InRelease                                                                                                                                                            
  Unknown error executing apt-key
Get: 2 http://us.archive.ubuntu.com/ubuntu focal-updates InRelease [114 kB]                                                                                                                                        
Err http://us.archive.ubuntu.com/ubuntu focal-updates InRelease                                                                                                                                                    
  Unknown error executing apt-key
Get: 3 http://us.archive.ubuntu.com/ubuntu focal-backports InRelease [101 kB]                                                                                                                                      
Err http://us.archive.ubuntu.com/ubuntu focal-backports InRelease                                                                                                                                                  
  Unknown error executing apt-key
Get: 4 http://us.archive.ubuntu.com/ubuntu focal-security InRelease [114 kB]                                                                                                                                       
Err http://us.archive.ubuntu.com/ubuntu focal-security InRelease                                                                                                                                                   
  Unknown error executing apt-key
Fetched 593 kB in 14s (40.9 kB/s)                                                                                                                                                                                  
W: GPG error: http://us.archive.ubuntu.com/ubuntu focal InRelease: Unknown error executing apt-key
E: The repository 'http://us.archive.ubuntu.com/ubuntu focal InRelease' is not signed.
W: GPG error: http://us.archive.ubuntu.com/ubuntu focal-updates InRelease: Unknown error executing apt-key
E: The repository 'http://us.archive.ubuntu.com/ubuntu focal-updates InRelease' is not signed.
W: GPG error: http://us.archive.ubuntu.com/ubuntu focal-backports InRelease: Unknown error executing apt-key
E: The repository 'http://us.archive.ubuntu.com/ubuntu focal-backports InRelease' is not signed.
W: GPG error: http://us.archive.ubuntu.com/ubuntu focal-security InRelease: Unknown error executing apt-key
E: The repository 'http://us.archive.ubuntu.com/ubuntu focal-security InRelease' is not signed.
E: Failed to download some files
W: Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/focal/InRelease: Unknown error executing apt-key
W: Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/focal-updates/InRelease: Unknown error executing apt-key
W: Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/focal-backports/InRelease: Unknown error executing apt-key
W: Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/focal-security/InRelease: Unknown error executing apt-key
E: Some index files failed to download. They have been ignored, or old ones used instead.

agagin run gpg --version , it shows:

gpg: Fatal: libgcrypt is too old (need 1.7.0, have 1.6.5)

and run apt-key update, it shows:

gpg: Fatal: libgcrypt is too old (need 1.7.0, have 1.6.5)

Try to reinstall libgcrypt

sudo apt-get install gnupg libgcrypt20 -o AllowUnauthenticated=true

comes out:

Reading package lists... Done
Building dependency tree       
Reading state information... Done
gnupg is already the newest version (2.2.19-3ubuntu2.1).
libgcrypt20 is already the newest version (1.8.5-5ubuntu1.1). ## the version installed is 1.8.5-5
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.

while run dpkg -p libgcrypt20,

Package: libgcrypt20
Priority: required
Section: libs
Installed-Size: 967
Origin: Ubuntu
Maintainer: Ubuntu Developers 
Bugs: https://bugs.launchpad.net/ubuntu/+filebug
Architecture: amd64
Multi-Arch: same
Version: 1.6.5-2  ## the version used is 1.6.5-2, which is not compatiable with the one installed 
Depends: libc6 (>= 2.15), libgpg-error0 (>= 1.14)
Suggests: rng-tools
Filename: pool/main/libg/libgcrypt20/libgcrypt20_1.6.5-2_amd64.deb
Size: 337608
MD5sum: 70d08ea8af8c6e037b17ac06682400c8
Description: LGPL Crypto library - runtime library
Original-Maintainer: Debian GnuTLS Maintainers 
SHA1: 4a3d1a02673f122dbb40093fb310c6ce11d6a6eb
SHA256: ef668b424efab479dbe3b7e99d697d9642d261e2c48d2b4fb5ddeabb321e6cbc
Homepage: http://directory.fsf.org/project/libgcrypt/
Description-md5: 5560adbd40c8ba1e5bc5596f9c536649
Supported: 5y
Task: minimal

So all the problems come from the wrong version of libgcrypt, solution can be as following:

locate libgcrypt

then move all .so files to another place and run

sudo ldconfig /usr/bin/gpg

if run gpg --version , it goes wrong again, move the .so file back
then it must show:

gpg (GnuPG) 2.2.19
libgcrypt 1.8.5
Copyright (C) 2019 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later 
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Home: /home/user/.gnupg
Supported algorithms:
Pubkey: RSA, ELG, DSA, ECDH, ECDSA, EDDSA
Cipher: IDEA, 3DES, CAST5, BLOWFISH, AES, AES192, AES256, TWOFISH,
        CAMELLIA128, CAMELLIA192, CAMELLIA256
Hash: SHA1, RIPEMD160, SHA256, SHA384, SHA512, SHA224
Compression: Uncompressed, ZIP, ZLIB, BZIP2

now the issuse is fixed, apt update and gnome-control-center is working

Note:
libgcrypt是一个非常成熟的加密算法库，也是著名的开源加密软件GnuPG的底层库，支持多种对称、非对称加密算法，以及多种Hash算法