July 3, 2022, I went to update link and got this error
W: failed to fetch http://packages.linuxmint.com/pool/main/m/mintupdate/mintupdate_5.8.4_all.deb Connection timed out [IP: 68.235.39.11 80]
To fix, I closed the Update Manager, and then I opened a terminal session and entered:
sudo apt update
Hit enter, and enter your password. It will update the system, minus the Mint Update Manager. Then relaunch the Update Manager and run it. Everything should install fine.
Problem solved.