Lexmark CS531
The printer serial number is listed as "UNKNOWN" when viewing reports displaying the printer usage in the Lexmark Cloud.
As the Lexmark cloud system matures, users should expect improved reporting, and less activity classified as "UNKNOWN".
LEGACY ID: FA1280
White Paper: Generating Printer Usage Reports for Cloud Fleet Management (CFM)
Known issues in the Lexmark Cloud Services 2019R3 release