Do you mean the registry entry "iaStorF"?
If you mean the registry entry, it gives the command to use the SCSI filter driver named iaStorF.sys. This is a big mistake, because the iaStorF.sys is not part of the "normal" Intel RST driverpacks v10.x.x.xxxx, v11.x.x.xxxx or v12.x.x.xxxx and has not been designed by Intel for being used together with the RST driver named iaStor.sys.What does it do!
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