EXFO iOLM - Manual (Page 150)

Managing Files
144 iOLM
Exporting OTDR Bellcore Files
3. The default file name is displayed in the File name field. You can edit
the file name and tap Save. If multiple wavelengths are present in the
iOLM file, then the wavelengths are appended in the file name while
you save the Bellcore (.sor) files.
Note: Depending on the type of unit you are using, the Save button may be
replaced with an OK button.
Note: Application provides the path in dialog box to save the OTDR Bellcore (.sor)
file on disk.
When you attempt to generate the .sor file and that the iOLM measurement
does not contain the necessary intermediate OTDR measurements, you
are notified that the file was not generated, and the reason why. If you
interrupt the generation of the .sor file, you are also notified that the file
was not generated.