HOWTO: Automate the UDMA Fix in Windows 98

ID: Q241459

The information in this article applies to:

Microsoft OEM Preinstall Kit (OPK), version 98

SUMMARY

Ultra Direct Memory Access (UDMA) is enabled by default in a Windows 98 preinstallation. This may cause shutdown problems, as well as difficulties when accessing the CD-ROM under non-DMA-enabled hardware. To resolve this problem, DMA must be disabled.

MORE INFORMATION

The following details the procedure for automatically disabling DMA in a preinstallation.

Extract the Mshdc.inf file from the Windows 98 CD-ROM into the C:\Temp folder of the reference computer using the following command at the MS-DOS prompt:

extract d:\win98\precopy2.cab /L c:\temp msbatch.inf
Note that d: is the CD-ROM drive letter.

Edit the Mshdc.inf file; the edited file must have the following lines commented out (or removed):
```
[ESDI_AddReg]
HKR,,IDEDMADRIVE0,3,01
HKR,,IDEDMADRIVE1,3,01 
```
Use a semi-colon (;) at the beginning of each line to comment out the line.

Copy the updated Mshdc.inf file into the A:\Pre_img\Factonly folder of the Preinstallation Boot Floppy (PBF).

Edit the Transfer.bat file under the A:\Pre_img\Factonly folder of the PBF as follows:
1. Locate this line in the Mshdc.inf file:
```
copy c:\factonly\%cfgdir%\msbatch.inf c:\windows\options\cabs 
```
2. Append the following new line after the line shown in step a:
```
copy c:\factonly\mshdc.inf c:\windows\options\cabs 
```
3. Save the Transfer.bat file.

Start the target computer with the PBF. The resulting preinstallation has DMA disabled.

REFERENCES

For preinstallation procedures, please refer to the Microsoft OEM System Builder Web site.

For additional information about Ultra DMA, please click the article number below to view the article in the Microsoft Knowledge Base:

Q232545 Description of Ultra DMA

Additional query words:

Keywords : kbOPK kbDSupport
Version : WINDOWS:98
Platform : WINDOWS
Issue type : kbhowto