System 7: How to Change a File Sharing Password Remotely

Yes. You can connect to one Macintosh from another Macintosh on the same
AppleTalk network and change your password with the Set Password button,
provided that file sharing is enabled on your Macintosh. You must be using
AppleShare workstation software 2.0 or greater (included any System 6
versions) to access your System 7 Macintosh.

Follow these steps to change your password remotely:

1) Open the Chooser.

2) Select your Macintosh with the AppleShare workstation software.

3) Click the Set Password button.

4) Type your new password.

5) Press Tab and type the current password.

6) Click OK.

7) Type your new password to reconfirm your change.

6) Click OK.