> I'd send an encrypted zip file. That itself has a standards problem. Most people don't have anything more than the archive reader installed with the OS which

> I'd send an encrypted zip file. That itself has a standards problem. Most people don't have anything more than the archive reader installed with the OS which for Windows means nothing better than ZipCrypto is supported IIRC. ZipCrypto can be broken so trivially, that it isn't worth bothering with. 7zip and other tools support stronger methods, even with .zip archives, but many people can't read the result. There is also the good old key exchange problem as you are using symmetric encryption: you need a second channel to send the key over. Fine for friends and others you already have more than one contact route between, there are a number of ways to communicate after all, but not for general comms. It is scary how many people in a supposedly security aware industry I see sending encrypted archives by mail then sending the password in another mail, or sending the password and a link to the content hosted elsewhere in the same email.