Windows Administration
CMD.EXE
Configuration
- Enable file / path extension (see
help cmd
):
HKEY_LOCAL_MACHINE\Software\Microsoft\Command Processor\CompletionChar <-- 09 (tab)
HKEY_LOCAL_MACHINE\Software\Microsoft\Command Processor\PathCompletionChar <-- 09 (tab)
- Command Extension are enabled by default
HKEY_LOCAL_MACHINE\Software\Microsoft\Command Processor\EnableExtensions
- Delayed expansion is not enabled by default:
HKEY_CURRENT_USER\Software\Microsoft\Command Processor\DelayedExpansion
Other useful config tools:
- DOSHere
- Open a cmd prompt by right clicking on any directory in windows explorer
Device Management
View and Delete Unused Devices
Open a cmd.exe console:
> set devmgr_show_nonpresent_devices=1
> devmgmt.msc
In the Device Management Console, select show hidden devices. Unused devices are grayed out.
Convert Logical Drive Letter to PhysicalDrive
The following C program illustrates what Win32 API to use to convert a logical drive letter like C: to the corresponding PhysicalDrive specification.
#include <stdio.h>
#include <w32api/wtypes.h>
#include <w32api/ddk/ntdddisk.h>
int main()
{
HANDLE hDeviceHandle = NULL;
char drive[] = {'\\', '\\', '.', '\\', 'A', ':', 0};
DWORD driveMask = GetLogicalDrives();
for(int i = 0; i < 26; i++)
{
drive[4] = 'A' + i;
printf("Drive: %s\n", drive);
hDeviceHandle = CreateFile(drive , 0, 0, NULL,
OPEN_EXISTING,FILE_ATTRIBUTE_NORMAL, NULL);
if (hDeviceHandle != (HANDLE)-1)
{
STORAGE_DEVICE_NUMBER sdn;
DWORD returned;
if (DeviceIoControl(
hDeviceHandle,IOCTL_STORAGE_GET_DEVICE_NUMBER,NULL ,0,&sdn,sizeof(sdn),&returned,NULL));
{
printf("\tDevice type: %d number: %d partition: %d\n",sdn.DeviceType,
sdn.DeviceNumber, sdn.PartitionNumber);
if(sdn.DeviceType == 7)
printf("\t-->\t\\\\.\\PhysicalDrive%d\n",sdn.DeviceNumber);
}
}
}
return 0;
}
Compile with:
% gcc logicalToPhysicalDrive.cpp
Example of output:
Drive: \\.\C:
Device type: 7 number: 0 partition: 1
--> \\.\PhysicalDrive0
Patch file version resource
Some windows file have a specific resource record that stores release information on that specific file (like file version, company name, etc ). One can see this record by using the NT Explorer → right click → properties → Version panel.
It is quite easy to change the content of this record by using an Hex Editor such as UltraEdit. Just look for either of the hex string below in the file:
560053005F00560045005200530049004F004E005F0049004E0046004F00 // V.S._.V.E.R.S.I.O.N._.I.N.F.O.
460069006C006500560065007200730069006F006E // F.i.l.e.V.e.r.s.i.o.n.
Note that the version number (file version) given at the top of the Version panel is actually coded in hex. The example below gives a file version 1.2.3.4.
xx xx xx xx xx xx xx xx xx xx 56 00 53 00 5F 00 // xxxxxxxxxxV.S._.
56 00 45 00 52 00 53 00 49 00 4F 00 4E 00 5F 00 // V.E.R.S.I.O.N._.
49 00 4E 00 46 00 4F 00 xx xx xx xx xx xx xx xx // I.N.F.O.xxxxxxxx
xx xx xx xx 02 00 01 00 04 00 03 00 xx xx xx xx // xxxx........xxxx
Shutting Down / Locking
Using rundll32.exe (see [1]):
rundll32.exe user32.dll,LockWorkStation
Another one:
rundll32.exe shell32.dll,SHExitWindowsEx [0|1|2|4|8]
:: 0: logoff, 1: shut down, 2: reboot, 4: forced shutdown, 8: powers down the machine
Regedit
Command-line
Using regtool (cygwin):
regtool /s registry_file.reg ;Silent merge registry file (no user confirmation)
Using reg.exe (windows):
;Silent merge
regedit /s registry_file.reg
;Create a global USER environment variable (persistent)
SET MYROOT="%CD"
echo Setting global USER Environment variable to %MYROOT%
reg add HKCU\environment /v MYROOT /t REG_SZ /d %MYROOT% /f
Regedit .reg File Format
See also Microsoft's reference page, here, here, here and on Wikipedia.
See also regtool chapter on Cygwin page.
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SYSTEM\Setup]
@=dword:00000000
"SetupType"=dword:00000000
"CmdLine"="setup -newsetup"
"SystemPrefix"=hex:c5,0b,00,00,00,40,36,02
; Comments are created with a semi-colon
; Delete a value by assigning a minus to it
"SetupType"=-
; Delete a key by preceding the name with a minus sign
[-HKEY_LOCAL_MACHINE\SYSTEM\Setup]
The header line indicates the version and can be either
Windows Registry Editor Version 5.00 for Windows 2000, Windows XP, and Windows Server 2003 REGEDIT4 for Windows 98 and Windows NT 4.0 (but is also accepted in 2000, XP or 2003)
Network
Detect Network Environment Change
The following VBS script can be used to detect automatically when a network cable is connected or disconnected ("network cable unplugged"), as in [2]. Some explanations at [3], and more on [4].
Use MSNdis_StatusMediaDisconnect to detect when a cable is unplugged.
Set colMonitoredEvents = GetObject("winmgmts:root\wmi")._
ExecNotificationQuery("Select * from MSNdis_StatusMediaConnect")
Do
Set strLatestEvent = colMonitoredEvents.NextEvent
WScript.Echo "Connected! Do something here"
' enable the line below if you want to exit after the first event.
' Exit Do
Loop
Same script a bit improved in order to limit detection to some specific adapter:
Set colMonitoredEvents = GetObject("winmgmts:root\wmi")._
ExecNotificationQuery("Select * from MSNdis_StatusMediaConnect" _
& " WHERE InstanceName = '3Com 10/100 Mini PCI Ethernet Adapter'")
Do
Set strLatestEvent = colMonitoredEvents.NextEvent
WScript.Echo "Connected! Do something here"
' enable the line below if you want to exit after the first event.
'Exit Do
Loop
Rename / Delete locked files using Registry
This uses a registry data called PendingFileRenameOperations in key [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager]. This data is a REG_MULTI_SZ. The syntax is as follows:
\??\source file !\??\target file
To delete a file, target file must be the null string, i.e. 00 00. For instance the registry file below can be used to delete a file named c:\TEMP\Kill-ME.eXe.
REGEDIT4
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager]
"PendingFileRenameOperations"=hex(7):5C,3F,3F,5C,63,3A,5C,54,45,4D,50,5C,4B,69,6C,6C,2D,4D,45,2E,65,58,65,00,00,00
Another way is to use the windows program reg.exe.
Tips
Re-Enable Hibernate Option (Vista)
On Vista, Hibernation is disabled after running the disk cleanup wizard and removing the hibernate files. To re-enable (see [5]):
- Go to the command prompt icon in the Start menu under Accessories and right click the icon: click “Run as administrator”.
- Paste: “powercfg.exe /hibernate on” and hit Enter and also paste “powercfg -h on” and hit enter just to be safe.
- Open Control Panel and type in “Hibernate” in the Search.
- Click “Turn hibernation on or off”
- Click “Change advance power settings”
- Scroll to and expand the “Sleep” option.
- Select “Off” to the “Allow hybrid sleep” option.
- Scroll to and expand the “Power buttons and lid” option.
- Select “Hibernate” for the “Sleep button action” option.
- Select “Hibernate” for the “Start menu power button” option.
Enable Login Verbose Status
Reference: [6]
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System]
"VerboseStatus"=dword:00000001
Open Issue
Reduce volume size after updates and service packs
Particularly true for Windows Vsta. Ideas:
- Can we use sysprep tool?
Troubleshoot
Windows 7 Boot Issues
See Windows 7 boot troubleshooting.
Network Connection Folder is Empty
Reference [7]
- Open registry editor, and go to key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Network,
- Delete the binary value Config,
There is no normally no need to restart the computer.