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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