Update Manager could not download all repository indexes

[dntc0x]

Describe the bug Update Manager could not download all repository indexes

• I am not a software developer, but a user who keeps getting the following error from Update Manager in Linux Mint 20.2. Please forgive me if this is not the proper place to get help on this issue.

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Distribution:

• [x] Linux Mint
• [ ] LMDE
• [ ] Other (please specify)

Software version: See Help > About in Update Manager.

• 5.8.4 Logs: Copy & paste the log output from Update Manager > View > Information here. 07.10@14:41 ++ Launching Update Manager 07.10@14:41 ++ Changes to the package cache detected, triggering refresh 07.10@14:41 ++ Starting refresh (local only) 07.10@14:41 ++ Initial refresh will happen in 0 day(s), 0 hour(s) and 10 minute(s) 07.10@14:41 ++ System is up to date 07.10@14:41 ++ Refresh finished 07.10@14:42 ++ Starting refresh (retrieving lists of updates from remote servers) 07.10@14:51 ++ Update Manager window is open, skipping initial refresh 07.10@14:51 ++ Recurring refresh will happen in 0 day(s), 1 hour(s) and 48 minute(s) 07.10@15:28 ++ Refreshing available Cinnamon updates from the server 07.10@15:28 ++ System is up to date 07.10@15:28 ++ Refresh finished 07.10@15:38 ++ Starting refresh (retrieving lists of updates from remote servers) 07.10@15:43 ++ Refreshing available Cinnamon updates from the server 07.10@15:43 ++ System is up to date 07.10@15:43 ++ Refresh finished Crash report: If you are reporting a crash, please run mintupdate from a terminal window, reproduce the crash and copy & paste any output from the terminal window here.
• No crash, just a recurring error

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[xenopeek]

If you need help with troubleshooting this please use the user support forums: https://forums.linuxmint.com/

If you followed the Brave installation instructions https://brave.com/linux/ you should not be getting this error. This error indicates the brave-browser-archive-keyring.gpg file is not installed or is not configured correctly for the Brave software repository. Update Manager is not the cause. The file is required for your package management system to be able to verify the integrity and authenticity of downloads from the Brave software repository.