Recover-deleted-messages-on-discord -

Local scripts that cache your own chat history as you use the app.

Bots like Dyno or MEE6 can be configured to log message events to a private moderator channel. recover-deleted-messages-on-discord

Request your Discord data package every few months to maintain a local archive of your existing history. Requesting a Copy of your Data - Discord Support Local scripts that cache your own chat history

Official way to monitor servers. Cons: Only works if the bot was active before deletion. BetterDiscord Plugins recover-deleted-messages-on-discord

For individual DMs, take screenshots of important conversations as they occur.