This error indicates that the game client was unable to read required data from storage.
In most cases, it is caused by corrupted game files, storage device issues, or third-party software interfering with file access.
Please follow the steps below in the given order.
1. Verify game file integrity
Corrupted or incomplete game files are the most common cause of file read errors.
- Use the game launcher’s file verification feature.
If you are using the Steam version, open Steam → Library → right-click the game → Properties → Installed Files → Verify integrity of game files.
This process will check existing files and re-download any damaged or missing data.
2. Delete the local cache folder
Cached data may become corrupted and cause repeated read failures.Delete the cache folder located in one of the following paths (depending on your installation):
C:\Program Files (x86)\WarThunder\cache
C:\Program Files (x86)\Steam\steamapps\common\War Thunder\cache
C:\Users\<YourUsername>\AppData\Local\WarThunder\cache
Note: The cache folder will be recreated automatically when you start the game again.
3. Check available disk space
Insufficient free space can cause file read and update failures.Ensure that the game installation drive has at least several gigabytes of free space. Low disk space can prevent proper file caching and patching.
4. Check the game installation drive for errors
File read errors often occur when Windows cannot read data from the storage device due to filesystem corruption or failing sectors.
Option 1: Run CHKDSK via Command Prompt
- Identify the drive where the game is installed (e.g. C:, D:, E:) and determine whether it is an HDD or SSD.
- Right-click the Windows icon and select Run.
- Type cmd, then press Ctrl + Shift + Enter to run the Command Prompt as administrator.
- Click Yes when prompted by User Account Control.
- Enter the appropriate command (replace c: with game installation drive letter):
For HDD: chkdsk c: /r /f
For SSD: chkdsk c: /f
Note: The /r parameter scans for bad sectors and attempts recovery. SSD controllers manage bad blocks internally, so using /r on SSDs is not recommended. - If you see a message stating that the volume is in use, type Y and press Enter.
- Restart your computer. The disk check will run during startup.
Important: Any non-zero number of bad sectors, especially if the number increases over time, indicates physical disk deterioration.
Option 2: Run CHKDSK via Windows graphical interface
- Press Windows + E to open File Explorer.
- Select This PC.
- Right-click the drive where the game is installed and choose Properties
- Open the Tools tab.
- Click Check and follow the on-screen instructions.
Note: CHKDSK may not function correctly if certain low-level security software (e.g. Vanguard) is installed.
5. Check antivirus and security software
Third-party antivirus or endpoint security software may block or interrupt file access during gameplay.
- Temporarily disable your antivirus software and test if the issue is recurring.
- After testing, re-enable your security software.
- Add the game installation folder to the antivirus exclusion / whitelist.
C:\Program Files (x86)\WarThunder
C:\Program Files (x86)\Steam\steamapps\common\War Thunder
C:\Users\<YourUsername>\AppData\Local\WarThunder
6. External or removable drives
If the game is installed on:
- an external USB drive,
- an external SSD/HDD,
- or removable storage,
try reinstalling the game on an internal drive. External connections are more prone to intermittent read failures.
7. Advanced: Check drive health using SMART tools
Advanced users may use SMART monitoring utilities provided by the drive manufacturer or reputable third-party tools to check disk health. We do not provide support for these tools. If disk health warnings are reported, we strongly recommend reinstalling the game on a healthy storage device.
Note: If your system drive and game installation drive are different devices, consider checking both, especially if you experience Windows instability, blue screens, or failed Windows updates.
Note: Consider updating or reinstalling storage controller drivers via the motherboard or system manufacturer’s website.
8. Check Windows system file integrity
Corrupted Windows system components can occasionally affect file access, but this is not a common cause of file read errors.
- Open the Command Prompt as administrator (refer to Chapter 4 points 2-4)
- Run command:
DISM /Online /Cleanup-Image /ScanHealth - If corruption is found, run:
DISM /Online /Cleanup-Image /RestoreHealth - After completion, run:
SFC /scannow
If these commands fail, advanced users may consider (we do not provide support in that area):
- using restore health command with downloaded offline system image;
- a clean Windows installation
Otherwise consider contacting a qualified technician.
9. Advanced: Check for RAM issues
RAM problems are an uncommon cause of file read errors and should only be checked if all storage-related steps show no issues.
Before testing:
- reset BIOS/UEFI settings to defaults (this disables RAM overclocking);
- if possible, verify if the issue reproduces with one RAM module at a time;
- the same suggestion applies to following memory diagnostic
To run the Windows memory diagnostic:
- Open the Command Prompt as administrator (refer to Chapter 4 points 2-4)
- Type:
mdsched - Choose when to run the test and restart the computer. The scan will begin immediately after your computer restarts
- Depending on the test preset selected and the number of passes, the test will take anywhere from a few minutes to several hours. You can change these settings in Options (F1).
Note: If you have time, select multiple standard test passes (or 1-2 extended passes) to ensure your RAM can withstand sustained stress (e.g. leave it running overnight). By default, Windows runs the memory test in two passes.
After the test completes, view the results in: Event Viewer → Windows Logs → System → Source: MemoryDiagnostics-Results
If no errors are detected and issues persist, advanced users may try (we do not provide support in that area):
- further diagnostic with reputable third-party tools such as MemTest86;
- updating BIOS/UEFI firmware if available.
If errors are reported consider replacing faulty RAM module(s).
10. Summary
If none of the steps above resolve the issue, the most likely cause is hardware-level storage instability. In such cases, reinstalling the game on a different, healthy drive (preferably internal SSD) is strongly recommended.