re: Random e-mail from my sent folder

Sounds like your email account was hacked. Some hackers will use software to try and crack people's email passwords to send out spam via your email address (to gain access to your address book so that your friends will think that it was you who sent them an email). The email sent to to@zqlrbqcsb might have been some sort of test email.

Passwords that are simple (like abc123 or tiger321) are more likely to get hacked. Changing your email address password to something more difficult (capital and lower case letters, special characters $&@) will fix the problem and protect you from getting hacked in the future.

A butt email/accidental email is also a possibility.