In this way you can define the default directory for saving the measurement data.
Step 1: Select in the menu Tools >> Options...
Step 2: Select File Locations.
Step 3: Open the section Drawing support.
Step 4: Open the section LineStyle File.
Step 5: Double click on the specified directory and the File Explorer will open.
Step 6: In the File Explorer, select your directory where the measurement files are to be saved and click Select Folder.
Step 7: Apply the change by clicking OK.