Quick answer: Epic Games Launcher error codes cover five main areas — login errors (LS-0013, “Sign in failed” — clear webcache, check status.epicgames.com), installation errors (IS-DS01, IS-DS02 — run as administrator, disable antivirus during install), download errors (disk write error — run as administrator, check drive health), verification errors (“Verification failed” — verify via Library → three dots → Verify, add to antivirus exclusions), and Epic Online Services errors (“EOS not initialized” — run as administrator, reinstall EOS redistributable). Most Epic Games Launcher errors are fixed by running the launcher as administrator and clearing the web cache.
The Login That Failed Every Morning — and the Cache Folder That Fixed It
For two weeks, the Epic Games Launcher refused to sign me in every morning. The launcher would open, show the login screen, I would enter my credentials, and it would return “Sign in failed” with no further explanation. The Epic website worked fine — I could log in at epicgames.com without any problem. The launcher worked fine in the afternoon — after the third or fourth attempt, it would suddenly accept the same credentials it had rejected all morning. The pattern pointed to a cache issue rather than a server issue. I found the fix on the Epic Games support forums: navigate to C:\Users\[username]\AppData\Local\EpicGamesLauncher\Saved\webcache, delete the entire webcache folder, and relaunch. The login worked on the first attempt the next morning and every morning after.
That experience captures the most important thing about Epic Games Launcher error codes: the launcher’s web cache is the source of a disproportionate number of login, store, and connection errors. The Epic Games Launcher uses an embedded Chromium browser for its interface, and that browser accumulates cached data that can become corrupted or stale. Clearing the webcache folder is the first fix to try for any Epic Games Launcher error that involves the login screen, the store, or the launcher’s interface — before reinstalling the launcher, before resetting the account password, and before contacting Epic support.
How Epic Games Launcher Errors Are Generated
The Epic Games Launcher is built on an embedded Chromium browser (for the store and account interface) combined with a native Windows service (the Epic Games Launcher service, which handles downloads, installations, and game launches). Errors are generated by three layers: the Chromium browser layer generates login errors, store connection errors, and web cache errors when the embedded browser cannot reach Epic’s web services or when the cached browser data is corrupted. The launcher service layer generates installation errors (IS-DS01, IS-DS02), download errors (disk write errors), and update errors when the service cannot write files or communicate with Epic’s download servers. The Epic Online Services (EOS) layer generates EOS initialization errors when the EOS runtime — a separate component that provides online multiplayer services for EOS-enabled games — cannot start or cannot connect to Epic’s backend.
Unlike Steam, the Epic Games Launcher does not use a standardized numeric error code system for all errors — many errors appear as plain-language messages (“Sign in failed,” “Installation failed,” “Verification failed”) with an optional error code appended (LS-0013, IS-DS01). The error code, when present, identifies the specific subsystem that generated the error. The plain-language message identifies the operation that failed.
The 5 Epic Games Launcher Error Categories
1. Login and Authentication Errors — LS-0013 and Sign-In Failures
Login and authentication errors prevent signing in to the Epic Games account through the launcher. Common error messages: “Sign in failed” (generic authentication failure — the most common Epic login error), LS-0013 (launcher service authentication error — the launcher service cannot authenticate with Epic’s servers), “Your account credentials are invalid” (incorrect email or password), “Two-factor authentication code is invalid” (2FA code expired or incorrect), “Too many login attempts” (account temporarily locked after multiple failed attempts — wait 30 minutes).
The most effective first fix for any Epic login error is clearing the launcher’s web cache: close the Epic Games Launcher completely (right-click taskbar icon → Exit), navigate to C:\Users\[username]\AppData\Local\EpicGamesLauncher\Saved\webcache (the AppData folder is hidden — type the path directly in the Windows Explorer address bar), and delete the entire webcache folder. Relaunch the Epic Games Launcher. Also check Epic Games server status at status.epicgames.com — login servers undergo scheduled maintenance, and LS-0013 errors frequently appear during maintenance windows. If the Epic website (epicgames.com/id) accepts the credentials but the launcher does not, the webcache is the cause.
2. Installation Errors — IS-DS01, IS-DS02, and Launcher Setup Failures
Installation errors occur when the Epic Games Launcher cannot install itself or cannot install a game. Common error codes: IS-DS01 (installation service error — the Epic Games Launcher service cannot start or cannot write files), IS-DS02 (installation dependency error — a required component cannot be installed), “Installation failed” (generic installation failure — check the launcher’s log files for the specific cause). These errors appear during the initial Epic Games Launcher installation or during game installation.
For IS-DS01 and IS-DS02 errors during launcher installation: download the latest Epic Games Launcher installer directly from epicgames.com (not from a cached or third-party source), right-click the installer → Run as administrator, and temporarily disable antivirus software during installation — antivirus software frequently blocks the Epic Games Launcher installer’s service registration. For game installation errors: ensure the installation drive has sufficient free space (the Epic Games Launcher requires additional temporary space beyond the game’s listed size), run the launcher as administrator, and add the game’s installation folder to antivirus exclusions before starting the installation.
3. Download and Verification Errors — Disk Write Errors and File Corruption
Download and verification errors occur when the Epic Games Launcher cannot write game files to the installation drive or when downloaded files fail their integrity check. Common errors: disk write error (the launcher cannot write to the installation folder — permissions or drive issue), “Verification failed” (one or more game files do not match the expected checksum — corrupted download or antivirus quarantine), “The following file is corrupted” (specific file identified as corrupted during verification).
For disk write errors: run the Epic Games Launcher as administrator (right-click the launcher shortcut → Run as administrator). Add the game’s installation folder and the Epic Games Launcher folder (C:\Program Files (x86)\Epic Games) to antivirus exclusions. Check drive health with CrystalDiskInfo — a drive with reallocated sectors causes repeated download and verification failures. For verification failures: go to Library → click the three dots (⋯) on the game → Verify — the launcher will re-download any files that fail the check. If the same files fail verification repeatedly after re-downloading, antivirus is quarantining them — check the antivirus protection history and restore quarantined files.
4. Launcher Update Errors — Self-Update Failures and Version Conflicts
Launcher update errors occur when the Epic Games Launcher cannot update itself to the latest version. The Epic Games Launcher updates automatically on launch — if the update fails, the launcher may display an error and close, or it may launch in an outdated state that cannot connect to Epic’s servers. Common update error messages: “The Epic Games Launcher failed to install an update,” “Unable to update the Epic Games Launcher,” “A newer version of the Epic Games Launcher is required.”
For launcher update errors: run the launcher as administrator — the update process writes files to the Program Files directory, which requires administrator privileges. Add the Epic Games Launcher folder to antivirus exclusions — antivirus software frequently blocks the launcher’s self-update process. If the launcher cannot update through the automatic process, download the latest installer from epicgames.com and run it over the existing installation — the installer will update the launcher without removing installed games. For persistent update failures, perform a clean reinstall: uninstall the launcher via Windows Settings → Apps, delete the C:\Program Files (x86)\Epic Games folder and the C:\Users\[username]\AppData\Local\EpicGamesLauncher folder, then reinstall from epicgames.com.
5. Epic Online Services Errors — EOS Not Initialized and Multiplayer Failures
Epic Online Services (EOS) errors prevent online multiplayer in games that use EOS as their online backend. EOS is a separate runtime component from the Epic Games Launcher — it is installed alongside EOS-enabled games and provides cross-platform online services (matchmaking, voice chat, friends, achievements) for games including Fortnite, Rocket League, Fall Guys, and many third-party titles. Common EOS errors: “EOS not initialized” (the EOS runtime failed to start), “Failed to initialize Epic Online Services” (EOS cannot connect to Epic’s backend), “EOS overlay failed to initialize” (the EOS in-game overlay — which provides the friends list and voice chat UI — cannot start).
For EOS errors: check Epic Games server status at status.epicgames.com — EOS outages affect all EOS-enabled games simultaneously. Run both the game and the Epic Games Launcher as administrator. Verify the game files through the launcher (Library → three dots → Verify). Reinstall the EOS redistributable: navigate to the game’s installation folder, find the Redist, Prerequisites, or Engine\Extras\Redist\en-us subfolder, and run EpicOnlineServicesInstaller.exe or EOSUI.exe. Disable overlay applications (Discord overlay, GeForce Experience overlay, MSI Afterburner overlay) that may conflict with the EOS overlay — disable one at a time to identify the conflicting application.
How to Fix Epic Games Launcher Errors: Step-by-Step
Step 1: Check Epic Games Server Status
Before attempting any local fix, check Epic Games server status at status.epicgames.com. Epic provides real-time status for each service: Epic Games Store, Epic Games Launcher, Epic Online Services, and individual game services (Fortnite, Rocket League). If any relevant service is degraded or undergoing maintenance, wait for Epic to resolve the issue. Login errors, download errors, and EOS errors that appear during a service outage cannot be resolved locally — they resolve automatically when the service is restored.
Step 2: Clear the Web Cache and Restart as Administrator
Close the Epic Games Launcher completely: right-click the Epic Games Launcher icon in the system tray → Exit. Open Task Manager (Ctrl+Shift+Esc) and ensure no Epic Games Launcher processes remain running — end any that do. Navigate to C:\Users\[username]\AppData\Local\EpicGamesLauncher\Saved\webcache (type the path directly in the Windows Explorer address bar — the AppData folder is hidden). Delete the entire webcache folder. Right-click the Epic Games Launcher shortcut → Run as administrator. This two-step process (webcache clear + administrator mode) resolves the majority of login errors, store connection errors, and launcher interface errors.
Step 3: Add Epic Games Folders to Antivirus Exclusions
Antivirus software is the most common cause of Epic Games Launcher installation failures, download errors, and verification failures. Add the following folders to antivirus exclusions before installing or downloading games: C:\Program Files (x86)\Epic Games (the launcher installation folder), the game installation folder (wherever you chose to install games — default is C:\Program Files\Epic Games\[GameName]), and C:\Users\[username]\AppData\Local\EpicGamesLauncher (the launcher’s data folder). In Windows Security: Virus and threat protection → Manage settings → Exclusions → Add or remove exclusions → Add a folder. After adding exclusions, verify game files (Library → three dots → Verify) to restore any previously quarantined files.
Step 4: Verify Game Files
For game-specific errors (launch failures, in-game crashes, “Verification failed” messages): verify the game’s files through the Epic Games Launcher. Open the Epic Games Launcher → Library → click the three dots (⋯) on the affected game → Verify. The launcher will check each game file against its expected checksum and re-download any files that fail the check. This process takes 5–30 minutes depending on the game size and drive speed. After verification completes, attempt to launch the game. If verification fails repeatedly on the same files, antivirus is quarantining those files — check the antivirus protection history, restore the quarantined files, and add the game folder to exclusions before verifying again.
Step 5: Reinstall the Launcher or Contact Epic Support
For persistent errors that are not resolved by clearing the webcache, running as administrator, adding antivirus exclusions, and verifying game files: perform a clean reinstall of the Epic Games Launcher. Uninstall the launcher via Windows Settings → Apps → Epic Games Launcher → Uninstall. After uninstalling, manually delete the C:\Program Files (x86)\Epic Games folder and the C:\Users\[username]\AppData\Local\EpicGamesLauncher folder — the uninstaller does not remove these folders. Download the latest installer from epicgames.com and install. Your installed games are not affected by reinstalling the launcher — the launcher will detect existing game installations. For account-specific errors (suspended account, payment disputes, 2FA lockout), contact Epic Games Support at epicgames.com/help.
Frequently Asked Questions About Epic Games Launcher Errors
What are the most common Epic Games Launcher errors?
The most common Epic Games Launcher errors are “Sign in failed” / LS-0013 (login error — clear webcache and check status.epicgames.com), IS-DS01 / IS-DS02 (installation error — run as administrator and disable antivirus), disk write error (download error — run as administrator and check drive health), “Verification failed” (file integrity error — verify via Library → three dots → Verify and add to antivirus exclusions), and “EOS not initialized” (Epic Online Services error — run as administrator and reinstall EOS redistributable).
How do I fix Epic Games Launcher login errors?
Check status.epicgames.com first. If servers are operational: close the launcher completely, delete the webcache folder (C:\Users\[username]\AppData\Local\EpicGamesLauncher\Saved\webcache), and relaunch as administrator. If the Epic website accepts your credentials but the launcher does not, the webcache is the cause. For “Too many login attempts,” wait 30 minutes before trying again.
How do I fix Epic Games game verification errors?
Go to Library → click the three dots on the game → Verify. If the same files fail verification repeatedly after re-downloading, antivirus is quarantining them — check the antivirus protection history, restore quarantined files, and add the game’s installation folder to antivirus exclusions before verifying again. Run the launcher as administrator before verifying.
How do I fix Epic Online Services (EOS) errors?
Check status.epicgames.com for EOS outages. Run the game and launcher as administrator. Verify game files. Reinstall the EOS redistributable from the game’s installation folder (Redist or Prerequisites subfolder → EpicOnlineServicesInstaller.exe). Disable overlay applications (Discord, GeForce Experience) one at a time to identify conflicts.
How do I completely reinstall the Epic Games Launcher without losing games?
Uninstall via Windows Settings → Apps → Epic Games Launcher → Uninstall. Manually delete C:\Program Files (x86)\Epic Games and C:\Users\[username]\AppData\Local\EpicGamesLauncher. Reinstall from epicgames.com. The launcher will detect existing game installations — your games are not deleted by reinstalling the launcher. You will need to sign in again after reinstalling.
Epic Games Launcher Error Fix Complexity and Cost
The table below summarizes common Epic Games Launcher errors, their typical cause, and the fix complexity and cost. All Epic Games Launcher errors are resolved at zero cost through software fixes — hardware costs apply only when the installation drive is failing.
| Error / Issue | Common Cause | DIY Fix Cost (USD) | Hardware / Service Cost (USD) |
|---|---|---|---|
| Sign in failed / LS-0013 | Corrupted webcache or server maintenance | $0 (clear webcache / check server status) | $0 |
| IS-DS01 / IS-DS02 — Install error | Permissions or antivirus blocking installer | $0 (run as admin / disable antivirus) | $0 |
| Disk write error (permissions) | Write permission denied — not running as admin | $0 (run launcher as administrator) | $0 |
| Disk write error (drive failing) | Failing storage drive with bad sectors | $0 (move game library to healthy drive) | $50 – $150 (replacement SSD) |
| Verification failed | Antivirus quarantine or corrupted download | $0 (restore quarantine / add exclusion / verify) | $0 |
| Launcher update failed | Permissions or antivirus blocking update | $0 (run as admin / add exclusion / reinstall) | $0 |
| EOS not initialized | EOS runtime not installed or overlay conflict | $0 (reinstall EOS redistributable / disable overlays) | $0 |
| Account suspended / 2FA lockout | Terms of Service violation or lost 2FA device | $0 (contact Epic Support at epicgames.com/help) | $0 |
Note: All Epic Games Launcher errors are resolved at zero cost through software fixes. The only hardware cost scenario is a failing storage drive causing persistent disk write and verification errors — CrystalDiskInfo (free, from crystalmark.info) identifies this condition. Reinstalling the Epic Games Launcher does not delete installed games — the launcher detects existing installations after reinstalling.
Conclusion: The Epic Games Launcher Webcache Is the First Fix to Try
The login error that appeared every morning for two weeks was caused by a corrupted webcache folder — a fix that took 30 seconds once I knew where to look. That outcome is the most common Epic Games Launcher error scenario: the embedded Chromium browser accumulates cached data that becomes stale or corrupted, causing login failures, store connection errors, and launcher interface issues that look like server problems or account problems but are actually local cache problems. Clearing the webcache is the first fix to try for any Epic Games Launcher error that involves the login screen or the store interface.
Epic Games Launcher errors divide into clear categories with specific fix paths. Login errors → clear webcache, check server status, run as administrator. Installation errors → run as administrator, disable antivirus during install, add folders to exclusions. Download and verification errors → run as administrator, add to antivirus exclusions, check drive health, verify game files. Launcher update errors → run as administrator, add to exclusions, reinstall from epicgames.com. EOS errors → check server status, run as administrator, reinstall EOS redistributable, disable conflicting overlays. In each category, the fix path is specific and documented at epicgames.com/help.
The most effective preventive measures for Epic Games Launcher errors are: run the launcher as administrator by default (prevents the majority of permission-related errors), add the Epic Games folders to antivirus exclusions during initial setup (prevents quarantine-related installation and verification failures), clear the webcache folder monthly (prevents accumulated cache corruption from causing login and store errors), and keep at least 15% of the installation drive free (prevents disk space-related download failures). These four habits prevent the majority of Epic Games Launcher errors that users encounter.
Sources
- Epic Games Support — Epic Games Launcher Troubleshooting and Error Code Reference. Available at: epicgames.com/help
- Epic Games — Service Status and Outage Information. Available at: status.epicgames.com
- Epic Games — Epic Account Services and Two-Factor Authentication Management. Available at: epicgames.com/id
- Epic Games Developer Documentation — Epic Online Services (EOS) Integration and Troubleshooting. Available at: dev.epicgames.com/docs/epic-online-services
- CrystalMark — CrystalDiskInfo Hard Drive Health Monitoring Tool. Available at: crystalmark.info/en/software/crystaldiskinfo
