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Minifilter USB Properties Disappeared

whitemarewhitemare Member Posts: 1


We developed a minifilter driver that only attach USB volumes. I noticed something that when i load my filter driver with "fltmc load minifilt1" command USB properties are gone. Disk usage space bar is missing and when i right click and look usb properties there are 0 bytes disk space. It is not a problem for tracking I/O operations. Every operation seems just fine but this problem. Any idea how it occured? Is it related because i set a reparse point on USB? (I already looked tileinfo register value, it seems fine too.)

Thanks already!


  • Scott_Noone_(OSR)Scott_Noone_(OSR) Administrator Posts: 3,379

    It should just be calling GetDiskFreeSpaceEx, which ends up as an IRP_MJ_QUERY_VOLUME_INFORMATION. ProcMon say anything interesting?

    I'd also try to write a small app that calls GetDiskFreeSpaceEx and see if that fails as well.


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