Deadlock Replay “Partial Decompression Failure”: How to Fix It

Partial Decompression Failure means Deadlock couldn’t finish unpacking the replay data. It doesn’t automatically mean the match is lost. Start by checking whether another recent replay downloads successfully. If you play in a language other than English or use mods, check those settings before repeatedly downloading the same file.

The full message may look like this:

Unlike “Replay Not Ready for Download,” this error concerns processing replay data, not simply whether a download is available. A download reaching 100% doesn’t guarantee that unpacking succeeded.

Try downloading one other recent match, then close Deadlock before inspecting any files.

The options below include community workarounds, not guaranteed Valve fixes. Skip branches that don’t fit your setup, and change one thing at a time so you can tell what helped.

A language-dependent save-path problem can put replays under game/citadel_<language>/replays instead of game/citadel/replays. That makes a temporary English-language test useful, especially if several replays fail.

With Deadlock closed, open Steam → Library → Deadlock → Properties → General → Launch Options and temporarily add:

Save your existing launch options first; don’t erase unrelated settings or leave conflicting language flags. Launch the game and retry the affected match. Afterwards, remove the temporary flag or restore your previous setting.

If English makes no difference—or you already use it—move on. This workaround doesn’t mean every non-English client is currently broken.

If you installed mods that changed gameinfo.gi or its SearchPaths, test without those changes. Altered search paths can redirect replay files into an addons folder.

Use the mod’s documented uninstall or disable procedure with the game closed. Back up your custom settings first. Don’t paste a stranger’s gameinfo.gi into your installation or edit paths at random. If you never installed mods, skip this part.

To check the game’s installed files:

Verification can replace modified or damaged managed files, including changes you intended to keep. It checks the installation; it doesn’t repair a downloaded replay or guarantee that its server copy is available.

If the replay is stuck after a failed attempt, moving its local files aside can let you request it again. This is particularly useful when there’s no retry button.

Open Deadlock’s installation through Steam’s Browse local files option. The usual replay directory beneath it is:

Depending on language or mod settings, also check existing game/citadel_<language>/replays or game/citadel/addons/replays folders. These are alternative locations to inspect, not folders you need to create.

For a safe retry:

Don’t empty the whole replays folder. A working .dem from another match has nothing to do with this failure. If you can’t confidently match a file to the affected ID, leave it alone.

Keep the backup until you’ve confirmed that the new copy plays. This matters especially for older matches: downloading a replacement may no longer be possible.

This is an optional fallback, not a required cleanup step. Some failed downloads leave a compressed replay that an archive tool can still unpack. Others leave incomplete data—or no file at all.

With Deadlock closed, make a separate working copy of the affected .dem.partial. Try opening that copy as an archive in WinRAR. If it opens and extracts a .dem without errors, place the extracted file in the replay folder where that match’s file was found, preserving any existing same-name file in your backup first. Restart Deadlock and check the match.

Stop if extraction reports an error or produces no usable .dem. Don’t force an overwrite, and don’t mistake a file with a new extension for a repaired replay. Successful extraction is only the first check; the replay still needs to play in the game.

If several fresh replays still fail after testing English, removing your own mod-related changes and verifying the installation, you may be dealing with a client bug that these workarounds don’t cover. If just one match fails, keep the focus on that match rather than repeatedly reinstalling everything.

Keep any backup you have and try again later. Don’t disable security software or change unrelated network settings just because the message contains “failure.” The error alone gives no reason to do either.

If the message changes to “Replay Not Ready for Download,” you’re now facing an availability issue. Repeating extraction steps won’t make a missing server copy appear.