how do you send an email from someone else's email address

Question

how do you (A) send an email stating it's from someone else's (B) email, stating it is from B, with B's permission?

Answer 1

To grant a user permissions to send on your behalf in Outlook:

1. Click Tools > Options > Delegates.
2. Click Add.
3. Choose the mailbox from the Address Book.
4. If you need the user to have partial access to your mailbox, you can specify the access level on the next screen. If you only need to give Send On Behalf permissions to the user, choose None for each folder.
5. Click OK.

To send as another user that has granted you permission:

1. Open a new email.
2. Click Options > From
3. Click the From button that was added to the email and select "Other E-Mail Address"
4. Select the user's email from the address book.
5. Click OK and finish the email.

Answer 2

There are multiple possible ways. This can be done rather easily on any system that has a program called "telnet", unless some device blocks such connections. (For example, ISPs may prevent you from contacting remote mail servers. This is sometimes seen on "home"/"consumer" Internet connections.)

The number of computers that contain the "telnet" program is quite large, including a very large number of Unix systems, or systems running Windows 95 through Windows XP, and is addable on yet more systems including Windows Vista (and newer) and OS/2 3.0 (and quite possibly other versions too).

SMTP over Telnet shows the SMTP commands that can be typed in order to send a legitimate E-Mail message over the Internet. Anyone doing this needs to specify what E-Mail address the mail came from. In theory, they could type any E-Mail address.

In practice, some E-Mail servers will reject some E-Mail addresses, like E-Mail addresses that specify an organization that is known to use a different IP address than the IP address that is sending the E-Mail.

That has been a description that discusses some of the very technical description. Some different E-Mail programs will provide an easy-to-fill-out form, where a user can simply type whatever E-Mail address they want. For instance, E-Mail software called "pine" does not have such a field that can be filled out, unless the user goes through the list of options and changes the option that specifies whether such a field should be visibly provided. If the user wants to, then the user can type in another E-Mail address. The exact steps needed to accomplish such a task will vary based on which software people are using. (For instance, CConrad96's answer discusses information from a version of Microsoft Outlook.)