It’s always OK to send an invalid sender address. If you have a sensitive sender address, it’s even better to send this to someone else.
The sender address is an important data point for Google, as well as the recipient (who is usually your e-mail address). If this address is invalid, Google won’t see it. However, if it is, it makes it harder for others to find your email. Sending an invalid address to someone else sends a message to the person you want to send to, which has the potential to be a big red flag for them.
That’s why it’s smart to use a real address, not a fake one, otherwise you’re going to get a lot of spam. The “real” address is the one that’s going to be displayed when you’re actually signing up for something. Your sender address should be just an e-mail address, so the best way to prevent others from seeing it is to make it a plain text e-mail address.
Sending an invalid address to someone on their account, without their permission or knowledge, is a major violation of the privacy of their account. Sending an invalid address to someone on someone else’s account without their knowledge or permission is also a major violation of the privacy of a person’s account. This is why you should use a real address.
Sending an e-mail with an invalid sender address is very bad form. In fact, sending an e-mail with an invalid address is a violation of the law in almost every country. The U.S. Postal Service, for example, has a strict address verification system that you should follow when sending an e-mail.
Sending an e-mail with an invalid address would be a major violation of the law as well as the postal service’s address verification system, but that’s not the point. The point is it’s bad form to use an invalid address.
Sending an e-mail with an invalid address is actually a federal crime. The mail carrier will almost always have to look up the address to figure out the right one. Sending an e-mail with a non-existent address is punishable by up to a year in prison. Sending an e-mail with an invalid address can also result in the loss of your mail carrier’s license and/or the loss of your mail.
Sending an e-mail with an invalid address is not a federal crime, but it does make it impossible for a mail carrier to pick up your mail. So if you don’t have a valid address, you have to leave your mailing address empty for the mail carrier to find out what to send your mail to. If your address has an invalid address, your mail carriers will have to figure out how to find your mailing address, then send your mail to the wrong address, etc.
As far as we’re aware, the mail carriers don’t have any special powers, but the mail carriers’ licenses do require them to have an address for the Postal Service. So if the mail carrier cannot find your address, then he has to either leave your address blank, or else he has to leave your address for your mailbox to be found. And that mailbox may or may not be at your house.
So you end up with a lot of mail that is addressed to an address that is either invalid, or just a house. There are a couple of ways to get around this. If you are willing to pay for a mailing label and a postage stamp, you can mail your mail from a different address than your mailbox is registered to. Or you can register your mailbox at a second address for a certain amount of time. You can also sign up for the Postal Service’s mailing list.