Fixes, updates and uninstalling

Find the symptom, then work through its checks in order. Most problems come down to a file in the wrong folder, and the log file tells you which.

No BepInEx folders after starting the game

Start the game, quit, and open the BepInEx folder in your Ravenfield folder. No LogOutput.log there means BepInEx never started.

winhttp.dll and doorstop_config.ini sit directly beside ravenfield.exe, not inside a subfolder such as BepInEx_win_x64_5.4.23.5. Compare with the screenshot in Step 1.
You used the x64 zip. In File Explorer the x64 winhttp.dll shows 26 KB (26,112 bytes); the x86 one shows 22 KB and won't load in Ravenfield.
doorstop_config.ini still says enabled = true.
You started the copy you modded. In Steam, Manage > Browse local files must open the same folder you copied BepInEx into.
Your antivirus didn't remove winhttp.dll. Check its quarantine or protection history; if the file is there, restore it and allow it.
On Linux or Steam Deck, the winhttp override is set: see Linux and Steam Deck.

BepInEx works, but there's no ONLINE tile

Open BepInEx\LogOutput.log in Notepad and search for RaveM (Ctrl + F). What you find points to the fix:

In the log	What it means and what to do
`Loading [RaveM 1.7.1]`	RaveM loaded. If the tile is still missing, open `com.stixsworldhd.ravem.cfg` and check that `EnableRaveM` in `[1. General]` is `true`: when it's false the ONLINE tile is hidden on purpose.
`Error loading [RaveM 1.7.1]`	RaveM failed while starting; the rest of that line names what failed. Usually one of the eleven DLLs is missing or damaged: copy all eleven again from a fresh, verified download.
`Skipping [RaveM ...] because a newer version exists`	There are two copies of `RaveM.dll` somewhere under `plugins` (subfolders count). Delete the old one.
No RaveM line at all	BepInEx didn't find `RaveM.dll`. The DLLs are probably next to `ravenfield.exe` or in `BepInEx` itself: move all eleven into `BepInEx\plugins` as in Step 3.
No LogOutput.log	BepInEx itself isn't running: see No BepInEx folders after starting the game.

Also make sure Steam was running and signed in before you started the game.

Can't join, or friends can't find your lobby

The lobby shows VERSION. It runs a different RaveM protocol and can't be joined. Everyone needs RaveM 1.7.1.
The lobby isn't listed. Set the three filters to SHOW and press REFRESH. A FRIENDS ONLY or INVITE ONLY lobby won't show up for everyone: the host can use INVITE FRIENDS, or friends can join through the Steam overlay.
It says the match is in progress. That host doesn't allow joining in progress; the lobby becomes joinable when they return to the lobby.
A map or mod is missing. Use GET in the Workshop window, wait until every row says Downloaded, restart Ravenfield and join again.
Wrong password. Locked lobbies need the exact password the host set.

The match won't start

START MATCH reads WAITING FOR READY. The host has REQUIRE READY on. The READY counter lists who still has to press READY. A player who lacks the map sees GET THE MAP FIRST and has to get it first.
The automatic start keeps cancelling. With AUTO START WHEN READY on, anyone un-readying or joining stops the countdown. It never starts during a vote.
A banner reads WAITING FOR 2 PLAYERS TO LOAD. It names who is still loading and counts down. The match starts for everyone once all players have loaded, or anyway when the countdown ends: LoadTimeoutSeconds, 120 s by default, in [2. Network].

No map vote after a match

The host runs RaveM 1.7.1. Before 1.5.3 the host's game missed several kinds of match ending, so no vote opened after them. Match ends are detected by the host's game, and players' games wait for its result.
On the host's HOST GAME > VOTING tab, VOTE ON isn't OFF and VOTE AT MATCH END is ON.
In Spec Ops and Haunted the mission ends, and the vote opens, when the last player is down or, in Haunted, when every wave is survived. The host needs RaveM 1.6.1 or newer for that; before, one player's death ended the mission.

A vote that closes with no votes at all isn't broken: the next map in the host's MAP CYCLE list loads. See When nobody votes.

Killcam problems

No killcam at all. Check SHOW KILLCAMS in PREFERENCES > KILLCAM & SPAWNING, and that the host's MODE OPTIONS for this game mode have KILLCAM on. Killed by a bot or a vehicle? The host's KILLCAMS FOR BOT KILLS and KILLCAMS FOR VEHICLE KILLS decide those.
No final killcam at the end. The host's FINAL KILLCAM AT MATCH END has to be on, and so does your SHOW KILLCAMS.
It ends too early. Respawning ends a killcam. If the host has AUTO SPAWN on, the host's WAIT FOR THE KILLCAM (on by default) keeps it from cutting in, or switch off USE AUTO SPAWN for yourself. Backspace skips a killcam when the host allows it; Fire never skips.
A frozen killer or missing soldiers. Ravenfield stops animating AI soldiers no camera can see; RaveM keeps them animating within KEEP ANIMATING WITHIN (250 m), so raise it for long-range kills. Soldiers beyond RECORD SOLDIERS WITHIN (800 m) keep their last recorded pose, and only those within SHOW SOLDIERS WITHIN (150 m) of the killer or the victim appear at all.
No weapon in KILLER'S EYES. That's expected since 1.6.6: the game draws first-person weapons with a separate camera that the killcam doesn't recreate. The killer's shots still draw tracers. Inside an enclosed vehicle seat the killcam shows CINEMATIC instead.
The killcam plays, then you never respawn. Fixed in 1.6.5: players on clients couldn't respawn at all. The game respawns you in its next spawn wave, every RESPAWN TIME and only after 6 s dead; its own "SPAWNING AT" countdown shows when.
Replays bounce back and forth, or soldiers look like streaks. Fixed in 1.6.4 and 1.6.3: check the version label at the top right of ONLINE.

LAN games: can't find or join

The host allowed Ravenfield through the Windows firewall on private networks, or allowed UDP port 48780. Without that, no one can join.
Every PC uses the same LAN port: LanPort in [13. LAN] of the settings file, 48780 by default.
Every PC runs RaveM 1.7.1, and the Steam client is running. Offline mode is enough for LAN.
Not on the same network segment? Broadcasts don't cross routers. Use DIRECT CONNECT with an address from the host's LAN ADDRESS button; from then on that address is probed directly. Virtual LANs (ZeroTier, Hamachi, Radmin VPN) are probed on their own adapters, and DIRECT CONNECT works across them too.
Over the internet, the host forwards UDP 48780 on their router and players use DIRECT CONNECT with the host's public address.

On LAN, players state their own Steam ID, so a ban by Steam ID can be dodged there. Use a LAN password to keep strangers out.

Voice chat problems

Pick your microphone and its volume in Steam > Settings > Voice. RaveM uses Steam's microphone.
In PREFERENCES > VOICE CHAT SETTINGS, VOICE CHAT is ON and YOUR MIC moves when you talk. MIC TEST plays you back. On open mic, press AUTO-SET and talk for 4 seconds.
You're holding the right key: H for nearby players, ` for the team radio.
The host's rules allow it: VOICE CHAT on, TEAM RADIO on for the radio, and the DEAD PLAYERS rule decides who hears the dead. If your mic box reads VOICE MUTED BY HOST, the host silenced you.
Can't hear one person? Check their row on PLAYER VOICES, and the ONLY STEAM FRIENDS, HEAR ENEMIES and MUTE STEAM-BLOCKED filters.

Lag in big lobbies

The host runs every bot and moves every player's soldier, so the host's CPU and upload carry the whole match. Fewer bots help most.
Hosts: set HostUploadMbps in [2. Network] to about 70 % of your real upload speed (default 25). In a match, Insert shows the budget per player; if Send failures rises above 0, lower it.
Players: a higher SMOOTHING DELAY looks smoother on a bad connection, at the cost of a slight delay.

A RaveM key moved or does nothing

RaveM never uses a key that Ravenfield uses. At startup, and when you save new controls in Ravenfield's options, it compares its keys with your own Ravenfield bindings and moves any key that clashes to a free one, with a message on screen and in the log. To choose a different key, click its box in PREFERENCES and press the new key; keys Ravenfield uses are refused, and RaveM tells you which game action owns them.

Update RaveM

Close Ravenfield.
Download the new version and check its SHA-256.
Copy its DLLs into BepInEx\plugins and choose Replace the files in the destination.
Keep com.stixsworldhd.ravem.cfg: settings added in a new version start at their defaults, and yours stay as they were.

When a new version changes the network protocol, everyone in your group has to update together.

RaveM 1.7.1 uses network protocol 8, so it doesn't play with older versions: update your whole group. Since 1.6.4 only RaveM.dll changed; from 1.5.x, UltimateReplay.dll is new too (it records the killcams). Copying all eleven is the simplest way to update.

Hosts who changed the ballistics settings in the settings file's section 5: since 1.7.1 those apply offline only. Set the same values in HOST GAME > MODE OPTIONS > BALLISTICS for online matches.

Turn RaveM or BepInEx off

To switch off	Change this	Effect
RaveM only	`EnableRaveM = false` in `[1. General]` of `BepInEx\config\com.stixsworldhd.ravem.cfg`	The ONLINE tile is hidden and no RaveM code runs in matches. Other plugins keep working.
BepInEx and every plugin	`enabled = false` in `doorstop_config.ini` next to ravenfield.exe	Ravenfield starts exactly as if nothing were installed.

Edit with the game closed, and set the value back to true to switch it on again.

Uninstall completely

Remove RaveM

Close Ravenfield.
Delete the eleven RaveM DLLs from BepInEx\plugins (the list is in Step 3). If another plugin you use ships one of the same libraries, such as MEC.Pro.dll, keep that one.
Optional: delete com.stixsworldhd.ravem.cfg and any RaveM_ files and folders in BepInEx\config to remove your RaveM settings too.

Remove BepInEx

Close Ravenfield.
Delete these from the game folder: the BepInEx folder, winhttp.dll, doorstop_config.ini, .doorstop_version and changelog.txt.
Optional: in Steam, right-click Ravenfield > Properties > Installed Files > Verify integrity of game files.

Asking for help

If you're asked for more detail, switch on VERBOSE LOG in PREFERENCES first.
Make the problem happen, then quit the game.
Copy BepInEx\LogOutput.log somewhere safe right away: BepInEx rewrites it the next time the game starts.
Send the log with your RaveM version (top right of ONLINE) and what you did, via stixsworldhd.com.