The error "failed to load custom.dll from the list error code 126" is a common Windows issue that usually appears when launching a game, application, plugin, or mod. Error code 126 typically means that Windows cannot find the specified DLL file or one of its required dependencies. As a result, the affected program fails to start or crashes during launch. Fortunately, this problem is usually software-related and can be fixed using the methods below.
Method 1: Restart Your Computer
A simple restart can resolve temporary file access issues or background conflicts that prevent DLLs from loading properly
Close all programs
Restart your PC
Try launching the affected application again
Method 2: Reinstall the Affected Program or Game
If custom.dll belongs to a specific application, reinstalling it often restores missing or corrupted files
Open Control Panel → Programs and Features
Uninstall the program showing the error
Restart your PC
Reinstall the program from its official source
Launch the program to check if the error is resolved
Method 3: Install or Repair Required Dependencies
Many DLLs depend on Microsoft system libraries
Reinstall Microsoft Visual C++ Redistributables
Download the latest Visual C++ Redistributable (x86 and x64) from Microsoft
Install all required versions
Restart your computer
Update or Reinstall DirectX
Download the DirectX End-User Runtime
Install and reboot your system
Missing dependencies are one of the most common reasons for error code 126
Method 4: Restore custom.dll Automatically (Recommended)
If you want a fast and beginner-friendly solution, an automated DLL repair tool such as PcGoGo DLL Fixer can help.
Download PcGoGo DLL Fixer DLL Fixer
Download and install PcGoGo DLL Fixer DLL Fixer
Launch the program
Scan
Click Scan to detect missing or corrupted DLL files
Locate custom.dll in the results
Repair
Click Repair Now
Restart your PC
Restart your PC after the repair
This method is especially useful when manual fixes do not work or when multiple DLL dependencies are missing
Method 5: Check Antivirus or Windows Defender
Security software may mistakenly block or quarantine custom.dll
Open Windows Security
Go to Virus & threat protection
Check Protection history
Restore custom.dll if it was quarantined
Add the program's installation folder to exclusions
Restart your PC
Method 6: Repair System Files Using SFC and DISM
System corruption can prevent DLLs from loading correctly
Run SFC
Open Command Prompt as Administrator
Enter:
sfc /scannow
Wait for completion
Restart your PC
Run DISM (if needed)
Open Command Prompt as Administrator
Enter:
DISM /Online /Cleanup-Image /RestoreHealth
Restart your PC after completion
These tools repair damaged system components that may affect DLL loading
Method 7: Update Windows
Windows updates can replace missing system libraries and fix compatibility issues
Go to Settings → Windows Update
Click Check for updates
Install all available updates
Restart your PC
Method 8: Re-register custom.dll (Advanced Users)
If the DLL exists but is not properly registered, re-registering it may help
Open Command Prompt as Administrator
Run:
regsvr32 /u custom.dll
regsvr32 custom.dll
Restart your PC
Prevention Tips
To avoid DLL error code 126 in the future:
Install software only from trusted sources
Keep Windows and drivers updated
Avoid downloading DLL files from random websites
Add trusted programs to antivirus exclusions
Keep system dependencies up to date
Create restore points before major changes
Common Causes of custom.dll Error Code 126
Missing or deleted custom.dll
Corrupted DLL file
Incomplete or failed software/game installation
Missing dependencies (Visual C++ Redistributable, DirectX)
Antivirus or Windows Defender quarantining the DLL
Incorrect registry entries or DLL path
Conflicts with mods, plugins, or third-party tools
System file corruption
Conclusion
The "failed to load custom.dll from the list error code 126" error usually occurs due to missing DLL files, broken dependencies, security software interference, or system corruption. In most cases, reinstalling the affected program, repairing dependencies, or using an automated DLL repair tool can resolve the issue quickly. By following the methods in this guide, you can restore custom.dll, eliminate error code 126, and ensure your applications run smoothly again.
