This advanced option must be set in an initialization (.ini) file.
This advanced option is system specific and is read from teklastructures.ini. Generally, there is no need to modify system-specific settings. Do not modify them if you are not an administrator.
Example
set
XSUSERDATADIR=%LOCALAPPDATA%\Tekla Structures\<version number>.
For example, C:\Users\<user>\AppData\Local\Trimble\Tekla Structures\<version>\UserSettings.