How do I forget or change the username and password for file sharing?

1. I connected my MacBook (macOS 10.13 if it matters) to my Mac Pro fileshare using the username foo and the password. I tell Finder to save the password.

2. I want to disconnect from that server and login again but this time with username bar and bar's password.

Here's the problem: as soon as I press the Disconnect button in the Finder on my MacBook, it immediately reconnects as user foo. It does not stay disconnected.

How can I connect to an existing server with a different username and password?

Solution 1:

1. Go to the Finder’s Go menu and choose Utilities
2. Select Keychain Acces
3. Select the Login Keychain then select the network password or internet password for the printers and/or shares.
4. Hold down the “control” key and click the keychain entry. Select Delete.

Now, access your network resource (printer or share) and re-enter your new username and password when prompted.