signature from … is unknown trust

msys2 에서 패키지 설치중 아래와 같은 에러가 나면..

$ pacman -S mingw-w64-x86_64-muparser
resolving dependencies...
looking for conflicting packages...
 
Packages (1) mingw-w64-x86_64-muparser-2.3.2-2
 
Total Download Size:   0.16 MiB
Total Installed Size:  0.65 MiB
 
:: Proceed with installation? [Y/n]
:: Retrieving packages...
 mingw-w64-x86_64...   162.6 KiB  61.3 KiB/s 00:03 [#####################] 100%
(1/1) checking keys in keyring                     [#####################] 100%
(1/1) checking package integrity                   [#####################] 100%
error: mingw-w64-x86_64-muparser: signature from "David Macek <david.macek.0@gmail.com>" is unknown trust
:: File /var/cache/pacman/pkg/mingw-w64-x86_64-muparser-2.3.2-2-any.pkg.tar.zst is corrupted (invalid or corrupted package (PGP signature)).
Do you want to delete it? [Y/n]
error: failed to commit transaction (invalid or corrupted package (PGP signature))
Errors occurred, no packages were upgraded.

요렇게.. 해결..

$ rm -rf /etc/packman.d/gnupg
$ pacman-key --init
$ pacman -S msys2-keyring
$ pacman-key --populate msys2
$ pacman-key --refresh-keys
$ pacman -Syu