When I use sudo apt-get update, I get the following errors:
Err:1 http:/archive.ubuntu.com/ubuntu xenial InRelease Could not connect to localhost:4001 (127.0.0.1). - connect (111: Connection refused)Err:2 http:/archive.ubuntu.com/ubuntu xenial-security InRelease Unable to connect to localhost:4001:Err:3 http:/archive.ubuntu.com/ubuntu xenial-updates InRelease Unable to connect to localhost:4001:Reading package lists... 4%(process:2389): GLib-GIO-WARNING **: Invalid proxy URI 'http:/localhost:4001 ': Invalid URI 'http:/localhost:4001 'Reading package lists... DoneW: Failed to fetch http:/archive.ubuntu.com/ubuntu/dists/xenial/InRelease Could not connect to localhost:4001 (127.0.0.1). - connect (111: Connection refused)W: Failed to fetch http:/archive.ubuntu.com/ubuntu/dists/xenial-security/InRelease Unable to connect to localhost:4001:W: Failed to fetch http:/archive.ubuntu.com/ubuntu/dists/xenial-updates/InRelease Unable to connect to localhost:4001:W: Some index files failed to download. They have been ignored, or old ones used instead.What can I do to fix this?