Below is a set of proven solutions, listed from the simplest and most likely to fix the issue to more advanced methods. Please follow them in order.
Error code 13 in 3uTools (“Failed to access folder — Error code 13”) indicates the app lacks permission to read or write the folder it’s trying to use, or the folder is locked by another process or antivirus/security software. 3utools Failed To Access Folder Error Code 13
If the error happens during backup or when accessing files, the directory may be blocked. Change Backup Location: Below is a set of proven solutions, listed
Corrupted permissions inside the 3uTools directory can cause error 13. 3utools Failed To Access Folder Error Code 13
A specific Windows 10/11 security feature prevents unauthorized applications from writing to standard directories like Documents or Desktops. Step-by-Step Solutions to Fix Error Code 13