    AST RESEARCH, INC.        TECHNICAL BULLETIN # 1522          6-24-96

    TITLE: Manhattan P Trap A in DPTSCSI.SYS

    SUMMARY

       The Windows NT Disk Administrator may cause a TRAP A: IRQL NOT
       LESS OR EQUAL error in DPTSCSI.SYS.

       This issue affects the following systems: 501502, 501503,
       and 501830.

    ISSUE

       A TRAP A: IRQL NOT LESS OR EQUAL error may occur in DPTSCSI.SYS
       when the user starts and exits the Windows NT Disk Administrator
       several times in succession.

    BACKGROUND

       If Windows NT 3.51 Disk Administrator is started and exited several
       times in quick succession, Windows NT may return an invalid pointer
       to the DPT miniport driver for Windows NT, causing the TRAP A error.
       This problem will not occur during normal system operation.

    ACTION

       To resolve this issue, replace DPTSCSI.SYS, version 1JM (which
       ships with Windows NT and DPT Storage Manager version 1.EB) with
       DPTSCSI.SYS version 1K1 or newer.  All DPTSCSI.SYS drivers,
       version 1K1 or later, contain the necessary modifications to
       prevent this from happening.

       Download the latest version of DPTSCSI.SYS from DPT's FTP site
       (ftp.dpt.com).

       The current version is 1K4.  The archive name is NTMGR1K4.ZIP.
       The archive is located in /pub/techsup/windows_nt/x86.

       The archive also contains DPT Storage Manager for Windows NT,
       version 1.K4.  Install the DPT driver into

          %systemroot%\system32\drivers\dptscsi.sys

       overwriting the existing driver.

    NOTES

       1. In order for the DPTSCSI.SYS version 1K4 driver to work,
          the DPT 3224 SCSI HBA requires DPT firmware version 7C or later.
          As of this posting, the current release (shipping from AST) for
          the DPT firmware is version 7CH.

       2. The NTMGR1K4.ZIP archive is password-protected.  Use the password
          "SKI" to unzip the file.  This password is case sensitive.

       3. Any time a Windows NT Service Pack 1, 2, 3 or 4 is installed,
          the current DPTSCSI.SYS driver will be overwritten with version
          1JM, which does not contain the necessary modifications.
          When this occurs, manually copy the new DPTSCSI.SYS driver v1K4
          to:

             %systemroot%\system32\drivers

       4. Windows NT Service Packs 1, 2, 3 or 4 alone do not solve this
          problem.

    TAN 000839GS

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