XMS Error Codes

 Upon return from XMS Functions, the AX register indicates success or

     AX=0000H = success
     AX=0001H = failure

 When a function fails, the BL register will contain an error code.  All
 XMS error codes have bit 7 set; so BL will be >= 80H.

    BL   Meaning
    ▀▀▀  ▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀
    80H  Function not implemented
    81H  A VDISK device is detected (screws up allocations...)
    82H  An A20 error occurred

    8eH  General XMM driver error
    8fH  Unrecoverable XMM driver error

    90H  HMA does not exist
    91H  HMA is already in use
    92H  DX is less than /HMAMIN= parm
    93H  HMA is not allocated
    94H  A20 line is still enabled

    a0H  All extended memory is allocated
    a1H  All XMS handles are in use
    a2H  Invalid handle

    a3H  WSrcHandle is bad
    a4H  LSrcOffset is bad
    a5H  WDestHandle is bad
    a6H  LDestOffset is bad
    a7H  Length is invalid
    a8H  Invalid overlap in move

    a9H  Parity error
    aaH  Block is not locked
    abH  Block is locked
    acH  Lock count has overflowed
    adH  Lock failed

    b0H  A smaller UMB is available
    b1H  No UMBs are available
    b2H  UMB segment number is invalid
    90H  Attribute type undefined

See Also: XMS Functions
          Extended Memory Specification (XMS)
          DOS Functions