1) Check the file "config.sys": 

   a) In DOS, type "EDIT CONFIG.SYS"

   b) Look for the "exclude" line.  It should look like:  

        DEVICE=C:\DOS\EMM386.EXE NOEMS X=D000-D7FF

      If this line is different (eg. this line calls a memory manager 
      such as QEMM) disable the line by typing REM in front of if it, 
      add the above line, save and exit. 

2) Check the "c:\windows\system.ini" file for the following settings:

     [386enh]
     ...
     EMMExclude=D000-D7FF* 

   If these addresses don't work, try C800-CFFF, D800-DFFF, E000-E7FF, or
   E800-EFFF. 

   Type the same address in the [tahiti.drv] or [multisnd.drv] section, 
   for example: 

     [tahiti.drv]
     ...
     RAMADDR=D000

   If the error persists, try a different address.