Error message

OS is Windows Vista. Getting message "Unable to select TWAIN source". What is this?:
RiomarTech Support Guy System Info Utility version 1.0.0.2
OS Version: Microsoft® Windows Vista™ Home Premium, Service Pack 2, 64 bit
Processor: Intel(R) Core(TM)2 Duo CPU T5800 @ 2.00GHz, Intel64 Family 6 Model 15 Stepping 13
Processor Count: 2
RAM: 4058 Mb
Graphics Card: Mobile Intel(R) 4 Series Express Chipset Family, 1805 Mb
Hard Drives: C: Total - 238472 MB, Free - 153868 MB;
Motherboard: Compal, 30F3
Antivirus: AVG Anti-Virus 2012, Updated and Enabled