During the installation of the SESMG model, Python packages could not be installed due to the presence of a special character (the German umlaut “ü”) in the Windows username. This caused encoding issues and file access errors (e.g., [WinError 5] Access Denied).

The problem was resolved by permanently enabling UTF-8 mode in Python using the command:

setx PYTHONUTF8 1

This forces Python to use UTF-8 encoding for all file paths and eliminates errors caused by special characters in Windows usernames.