' Visual Basic Script program to reset the DMA status of all ATA drives

' Copyright © 2006 Hans-Georg Michna

' Version 2007-04-04

' Works in Windows XP, probably also in Windows 2000 and NT.
' Does no harm if Windows version is incompatible.

If MsgBox("This program will now reset the DMA status of all ATA drives with Windows drivers." _
 & vbNewline & "Windows will redetect the status after the next reboot, therefore this procedure" _
 & vbNewline & "should be harmless.", _
   vbOkCancel, "Program start message") _
 = vbOk Then

RegPath = "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E96A-E325-11CE-BFC1-

08002BE10318}\"
ValueName1Master = "MasterIdDataChecksum"
ValueName1Slave = "SlaveIdDataChecksum"
ValueName2Master = "UserMasterDeviceTimingModeAllowed"
ValueName2Slave = "UserSlaveDeviceTimingModeAllowed"
ValueName3 = "ResetErrorCountersOnSuccess"
MessageText = "The following ATA channels have been reset:"
MessageTextLen0 = Len(MessageText)
ConsecutiveMisses = 0
Set WshShell = WScript.CreateObject("WScript.Shell")

For i = 0 to 999
 RegSubPath = Right("000" & i, 4) & "\"

 ' Master

 Err.Clear
 On Error Resume Next
 WshShell.RegRead RegPath & RegSubPath & ValueName1Master
 errMaster = Err.Number
 On Error Goto 0
 If errMaster = 0 Then
   On Error Resume Next
   WshShell.RegDelete RegPath & RegSubPath & ValueName1Master
   WshShell.RegDelete RegPath & RegSubPath & ValueName2Master
   On Error Goto 0
   MessageText = MessageText & vbNewLine & "Master"
 End If

 ' Slave

 Err.Clear
 On Error Resume Next
 WshShell.RegRead RegPath & RegSubPath & ValueName1Slave
 errSlave = Err.Number
 On Error Goto 0
 If errSlave = 0 Then
   On Error Resume Next
   WshShell.RegDelete RegPath & RegSubPath & ValueName1Slave
   WshShell.RegDelete RegPath & RegSubPath & ValueName2Slave
   On Error Goto 0
   If errMaster = 0 Then
     MessageText = MessageText & " and "
   Else
     MessageText = MessageText & vbNewLine
   End If
   MessageText = MessageText & "Slave"
 End If

 If errMaster = 0 Or errSlave = 0 Then
   On Error Resume Next
   WshShell.RegWrite RegPath & RegSubPath & ValueName3, 1, "REG_DWORD"
   On Error Goto 0
   ChannelName = "unnamed channel " & Left(RegSubPath, 4)
   On Error Resume Next
   ChannelName = WshShell.RegRead(RegPath & RegSubPath & "DriverDesc")
   On Error Goto 0
   MessageText = MessageText & " of " & ChannelName & ";"
   ConsecutiveMisses = 0
 Else
   ConsecutiveMisses = ConsecutiveMisses + 1
   If ConsecutiveMisses >= 32 Then Exit For ' Don't search unnecessarily long.
 End If
Next ' i

If Len(MessageText) <= MessageTextLen0 Then
 MessageText = "No resettable ATA channels with Windows drivers found. Nothing changed."
Else
 MessageText = MessageText & vbNewline _
   & "Please reboot now to reset and redetect the DMA status."
End If

MsgBox MessageText, vbOkOnly, "Program finished normally"

End If ' MsgBox(...) = vbOk

' End of Visual Basic Script program