Problem: Steam Deck games stuck on “Starting Launch” / “Preparing to launch” after a recent update (many titles won’t open)
Published: 2026-01-19 09:20 (local time)
Quick Summary
- After a SteamOS / Steam client update, some Steam Deck owners report that many (or all) games won’t start and hang on “Starting Launch” or “Preparing to launch.”
- It’s affecting both Steam games and, in some cases, non-Steam shortcuts (depending on the underlying cause).
- There isn’t one “official, universal fix” because the symptom can come from multiple root causes (Proton runtime issues, corrupted download/temp files, broken shader/compatdata links, plugins, or a bad update state).
- The most reliable workarounds reported by real users revolve around: verifying game files, deleting Proton files, changing Proton versions, disabling Steam Cloud temporarily, clearing broken compatdata/shadercache setups, and (as a last resort) reimaging SteamOS.
What’s happening
In late December 2025 into early January 2026, multiple Steam Deck users reported a frustrating failure mode where games never progress past the launch phase. Instead, the UI stays stuck on “Starting Launch,” or the game briefly attempts to start and returns to the Play button. Posts describing this exact “after update” behavior spiked around December 24, 2025, and similar “still happening” confirmations continue into early 2026 in older troubleshooting threads.
Symptoms commonly described include:
- Games hang indefinitely on “Starting Launch” (often after a recent update).
- Launching from Desktop Mode sometimes doesn’t help (still won’t open or immediately closes).
- Users report having tried typical first-line steps (reboots, verifying files, switching modes) without consistent success.
Who’s affected: primarily Steam Deck owners (SteamOS), across a variety of games (so it doesn’t look like a single game’s patch). The trigger is often described as “right after the latest update,” but not all users are on the same update channel or same installed software stack—one reason there’s no single fix.
Likely causes (what research suggests)
- Corrupted or incomplete runtime/game files after an update: Some fixes work only after Steam re-checks and re-downloads missing components. Community reports note that verifying a game can repair underlying Steam Linux Runtime / shared components that affect multiple titles.
- Proton prefix / compatdata or shadercache issues: If compatdata/shadercache folders were moved (or symlinked) to a microSD and the card fails or becomes unavailable, games can stop launching until the links are removed and regenerated.
- Proton or per-game Proton files in a bad state: Users report that deleting Proton files can break the “stuck launching” loop by forcing a clean rebuild of the game’s Proton environment.
- Steam Cloud sync conflicts: Some users report “starting launch” loops resolving after disabling cloud sync temporarily, suggesting a hang during sync/handshake for certain setups.
- Post-update instability requiring OS repair: Valve provides an official SteamOS recovery/reimage process, implying that some “stuck launching / broken state” cases are best resolved by repair/reimage when simpler steps fail.
Solutions & Workarounds
1) Verify integrity of game files (often repairs shared components)
Who it helps: Steam Deck (Steam games), especially if many games fail right after an update.
Steps:
- Open your Library and select a small game you have installed (faster to verify first).
- Open the game’s Properties.
- Go to “Installed Files” and choose “Verify integrity of game files.”
- When done, try launching multiple affected games again.
Risks / tradeoffs: May re-download files; takes time and storage bandwidth.
Stop & contact support when: Verification repeatedly fails, or you see storage errors and nothing launches after multiple verifies.
2) Delete Proton files for the affected game (forces a clean Proton rebuild)
Who it helps: Steam Deck games stuck on “Starting Launch,” particularly Proton titles.
Steps:
- Enable Developer Mode (Settings → System → enable Developer Mode).
- Open the affected game’s options menu.
- Use the “Delete Proton files” option (wording may vary by UI version).
- Launch the game again and allow time for the prefix to rebuild.
Risks / tradeoffs: Can remove the game’s Proton prefix, which may reset certain in-game settings; locally stored saves that aren’t cloud-synced could be at risk depending on the game.
Stop & contact support when: Multiple games remain stuck after rebuilding prefixes, or the Deck begins showing wider system instability.
3) Temporarily disable Steam Cloud for the problem game
Who it helps: Users who suspect a cloud sync hang (especially when launch attempts always stall at the same point).
Steps:
- Select the game in Library → Properties.
- Disable Steam Cloud sync for that game.
- Try launching the game.
- If it launches, re-enable Cloud later and resolve sync conflicts carefully.
Risks / tradeoffs: You may end up with diverging save versions (local vs cloud).
Stop & contact support when: You see repeated sync conflict prompts or missing saves you can’t recover.
4) Switch Proton version (Experimental vs a known-stable version)
Who it helps: Proton games that recently stopped launching after an update (or after a game patch).
Steps:
- Game → Properties → Compatibility.
- Force a specific Proton version (try Proton Experimental first, then a stable Proton release).
- Launch and test; keep notes so you can revert.
Risks / tradeoffs: Different Proton builds can fix one game and break another; may require shader re-caching.
Stop & contact support when: No Proton version launches anything and you suspect system corruption.
5) If you moved compatdata/shadercache to microSD: undo it (fix broken links)
Who it helps: Tinkerers who relocated compatdata/shadercache and later had SD card issues (bricked card, unmounted path, corrupted filesystem).
Steps:
- Boot Desktop Mode.
- Check whether compatdata/shadercache were symlinked to the microSD.
- If the target path is missing/unmounted, remove the broken links and restore defaults so Steam can regenerate them.
- Reboot and relaunch a small game to rebuild.
Risks / tradeoffs: Rebuilding can take time; may re-download shaders and increase internal storage use.
Stop & contact support when: The internal drive is failing, or filesystem errors persist after repairs.
6) Last resort: SteamOS Recovery / Reimage (official clean slate)
Who it helps: Decks stuck in a persistent broken state where many games won’t launch despite the above steps.
Steps (high level):
- Follow Valve’s SteamOS Recovery instructions to create recovery media.
- Boot the Deck into the recovery environment.
- Choose the least-destructive repair option first if available; if not, reimage as a full reset.
Risks / tradeoffs: Reimaging wipes data/settings; back up saves/screenshots first where possible.
Stop & contact support when: Reimage fails, the Deck won’t boot reliably, or inputs behave incorrectly—signs of hardware or deeper OS issues.
Prevention (so it doesn’t come back)
- Avoid moving core Steam folders (compatdata/shadercache) to microSD unless you understand symlinks and failure modes.
- After major updates, test-launch one small game first; if it fails, verify files before installing more updates.
- Be cautious with system plugins/mods (e.g., UI tweaks) and disable them when troubleshooting launch-wide issues.
- Keep enough free internal storage for shader caches and Proton prefixes; near-full storage can amplify update/verification failures.
FAQ
Q: Is this a single game bug?
A: Usually no—reports describe many games failing after an update, suggesting a runtime/Proton/SteamOS state issue rather than one title.
Q: Why does verifying one game sometimes fix multiple games?
A: Verification can trigger repairs/redownloads of shared components (runtime dependencies) that affect more than one title.
Q: Will “Delete Proton files” delete my save?
A: It can remove the Proton prefix. Many games keep saves elsewhere (often cloud-backed), but not always—back up first if you can.
Q: Should I switch to Beta/Preview updates to fix it?
A: Sometimes users report a channel switch helps, but it can also introduce new issues. Try safer steps first (verify/delete Proton files).
Q: If Desktop Mode also can’t launch games, is it hardware?
A: Not necessarily. It can still be OS/runtime corruption, broken links, or storage errors—try recovery/repair steps before assuming hardware failure.
Q: When should I stop troubleshooting?
A: If reimage/repair doesn’t stabilize things, or inputs/controls start behaving incorrectly, contact official Steam Support.