Gibt es GNU pretty good privacy nicht auch für Windows ?
Gnu Privacy Guard (GnuPG) Mini Howto
4.1 Verschlüsseln
Das Kommando zum Verschlüsseln lautet
gpg -e Empfänger [Datei]
oder
gpg --encrypt Empfänger [Datei]
Es ist sinnvoll, die Dateien auch zu signieren, genaueres siehe
Signaturen.
4.2 Entschlüsseln
Das Kommando zum Entschlüsseln lautet
gpg [-d] [Datei]
oder
gpg [--decrypt] [Datei]
Auch hier gilt: Voreingestellt ist Ausgabe auf stdout, man kann aber mit der Option -o [Datei] in eine Datei ausgeben.
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GPG2(1) GNU Privacy Guard GPG2(1)
NAME
gpg2 - OpenPGP encryption and signing tool
SYNOPSIS
gpg2 [--homedir dir] [--options file] [options] command [args]
DESCRIPTION
gpg2 is the OpenPGP part of the GNU Privacy Guard (GnuPG). It is a
tool to provide digital encryption and signing services using the
OpenPGP standard. gpg2 features complete key management and all bells
and whistles you can expect from a decent OpenPGP implementation.
In contrast to the standalone version gpg, which is more suited for
server and embedded platforms, this version is commonly installed
under the name gpg2 and more targeted to the desktop as it requires
several other modules to be installed. The standalone version will be
kept maintained and it is possible to install both versions on the
same system. If you need to use different configuration files, you
should make use of something like ‘gpg.conf-2’ instead of just
‘gpg.conf’.
RETURN VALUE
The program returns 0 if everything was fine, 1 if at least a signa-
ture was bad, and other error codes for fatal errors.
WARNINGS
Use a *good* password for your user account and a *good* passphrase to
protect your secret key. This passphrase is the weakest part of the
whole system. Programs to do dictionary attacks on your secret keyring
are very easy to write and so you should protect your "~/.gnupg/"
directory very well.
Keep in mind that, if this program is used over a network (telnet), it
is *very* easy to spy out your passphrase!
If you are going to verify detached signatures, make sure that the
program knows about it; either give both filenames on the command line
or use '-' to specify STDIN.
INTEROPERABILITY
...