INTRODUCTION
When a storage device is connected to Windows, even if only briefly, windows creates registry information for the device. Over time, the registry may contain many entries for devices that will never be used again. This article describes how to remove this information from the system registry.
It is the responsibility of the software that establishes the connection between the storage device and Windows to properly clean up the information for the device. This process is necessary because Windows does not know when a storage device is removed temporarily or permanently. But the software that establishes the connection typically does know this. For example, if backup software is mounting logical unit numbers (LUNs) for backup purposes and then unmounting the LUNs, it would be the responsibility of the backup software to clean up the LUN information from Windows, because the same storage device will no longer be used again by Windows.
More Information
When a new device is connected to a computer, Windows records information about the device in the system registry. For most devices, this procedure does not pose a problem. However, after a storage device is presented by a LUN through a fiber channel or through iSCSI, the device may never be encountered again by the computer. For example, a device might be identified by a serial number or by SCSI pages 0x80 and 0x83.Microsoft DevNodeClean utility.
In this situation, the registry may contain entries for devices that may never appear again. Not only do these entries occupy space in the registry, these entries may eventually cause operational problems. For example, because indexes for Plug and Play functionality use four-digit decimal values, a problem may occur when device 10,001 is connected. To resolve this limitation in Plug and Play functionality, you may want to remove device information from the registry when the device is a hard disk drive that is no longer present. You can do this by using theHow to build for Windows Server 2003, Windows Server 2008, Windows Server 2008 R2, and Visual Studio 2005
To clean the registry for the GUID_DEVCLASS_DISKDRIVE disk class GUID and for the GUID_DEVCLASS_VOLUME disk class GUID, follow these steps.DevNodeClean utility for this task. The following steps and the code example in step 7 are provided only for informational purposes.
Note We recommend that you use the-
Call the SetupDiGetClassDevs function to obtain information for the class that is associated with the GUID.
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Call the SetupDiEnumDeviceInfo function to obtain instance information for each device in the current class.
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Call the CM_Get_DevNode_Status function to see whether the current device information represents an absent device. Determine whether the function status is equal to CR_NO_SUCH_DEVINST or to CR_NO_SUCH_VALUE.
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Optionally, for an absent device, call the CM_Get_Device_ID function to obtain the device instance ID and to display the ID before you remove the information.
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For the absent device, use the class information that you obtained in step 1 and the instance information that you obtained in step 2. Call the SetupDiCallClassInstaller(DIF_REMOVE, …) function to remove the information from the registry.
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When all the devices in the current class have been handled, call the SetupDiDestroyDeviceInfoList function to clean up.
Note In some scenarios, you may have to clean the registry not only for the GUID_DEVCLASS_DISKDRIVE and GUID_DEVCLASS_VOLUME disk class GUIDs, but also for the GUID_DEVCLASS_SCSIADAPTER and GUID_DEVCLASS_VOLUMESNAPSHOT disk class GUIDs. To do this, you must change the DiskClassesToClean definition in the following sample code.
The following Win32 console application is an example of an application that cleans the registry. To use this application, follow these steps. Microsoft provides programming examples for illustration only, without warranty either expressed or implied. This includes, but is not limited to, the implied warranties of merchantability or fitness for a particular purpose. This article assumes that you are familiar with the programming language that is being demonstrated and with the tools that are used to create and to debug procedures. Microsoft support engineers can help explain the functionality of a particular procedure. However, they will not modify these examples to provide added functionality or construct procedures to meet your specific requirements.Â-
In Microsoft Visual Studio 2005, click New on the File menu, and then click Project.
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Expand Visual C++, and then click Win32.
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Click Win32 Console Application, type Cleanup in the Name text box, and then click OK.
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Click Finish in the Win32 Application Wizard dialog box.
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In Solution Explorer, expand Source Files, right-click Cleanup.cpp, and then click View Code.
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Locate the following code:
int _tmain(int argc, _TCHAR* argv[]) { return 0; }
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Replace the code that you found in step 6 with the following code.
/**************************************************************************************************/ /* */ /* Copyright (c) 2007 Microsoft Corporation. All Rights Reserved */ /* */ /**************************************************************************************************/ #pragma warning( disable : 4201 ) // nonstandard extension used : nameless strut/union #include <windows.h> #include <stdlib.h> #include <stdio.h> #include <stddef.h> #include <tchar.h> #include <setupapi.h> #include <cfgmgr32.h> #include <initguid.h> #include <devguid.h> #define SIZECHARS(x) (sizeof((x))/sizeof(TCHAR)) #define arraysize(p) (sizeof(p)/sizeof((p)[0])) CONST GUID *DiskClassesToClean[2] = { &GUID_DEVCLASS_DISKDRIVE, &GUID_DEVCLASS_VOLUME }; /**************************************************************************************************/ /* */ /* The user must be member of Administrator group and must have backup and restore permissions */ /* (SE_BACKUP_NAME and SE_RESTORE_NAME). No check for these is performed in this example. */ /* */ /**************************************************************************************************/ int __cdecl main( IN int ArgC, IN char * pArgV[] ) { HDEVINFO DeviceInfoSet; SP_DEVINFO_DATA DeviceInfoData; ULONG DevicesRemoved = 0, i, MemberIndex, Status, Problem, ulClassesToCleanIdx; BOOL bDoRemove = TRUE; CONFIGRET cr; TCHAR DeviceInstanceId[MAX_DEVICE_ID_LEN]; OSVERSIONINFO osvi; const GUID ** ClassesToClean; // // Parse parameters. // for (i = 1; i < (ULONG)ArgC; i++) { // // Check for help. // if ( (lstrcmpi(pArgV[i], TEXT("-?")) == 0) || (lstrcmpi(pArgV[i], TEXT("/?")) == 0) ){ printf("\nCleanUp will remove phantom storage device nodes from this machine.\n\n"); printf("Usage: CleanUp \n"); printf("\twhere /n displays but does not remove the phantom devnodes.\n"); printf("\nBackup and Restore privileges are required to run this utility.\n"); return 0; } // // Check for -n, which means just list the devices that we would remove. // if ( (lstrcmpi(pArgV[i], TEXT("-n")) == 0) || (lstrcmpi(pArgV[i], TEXT("/n")) == 0) ) { bDoRemove = FALSE; } } // // Run only on Windows XP/2003 (version 5.1) or later. // ZeroMemory(&osvi, sizeof(OSVERSIONINFO)); osvi.dwOSVersionInfoSize = sizeof(OSVERSIONINFO); if (!GetVersionEx(&osvi)) { printf("CleanUp: Unable to verify Windows version, exiting...\n"); return -1; } if ((osvi.dwMajorVersion == 5) && ((osvi.dwMinorVersion == 1) || (osvi.dwMinorVersion == 2))) { } else if (osvi.dwMajorVersion>=6) { } else { printf("CleanUp: This utility is designed to run on Windows XP/2003 and later\n"); return -1; } ClassesToClean = DiskClassesToClean; ulClassesToCleanIdx = arraysize(DiskClassesToClean); for (i=0; (i<ulClassesToCleanIdx) && (bDoRemove); i++) { DeviceInfoSet = SetupDiGetClassDevs(ClassesToClean[i], NULL, NULL, 0 ); if (INVALID_HANDLE_VALUE!=DeviceInfoSet) { DeviceInfoData.cbSize = sizeof(DeviceInfoData); MemberIndex = 0; while (SetupDiEnumDeviceInfo(DeviceInfoSet, MemberIndex++, &DeviceInfoData )) { // // Determine whether this device is a phantom. // cr = CM_Get_DevNode_Status(&Status, &Problem, DeviceInfoData.DevInst, 0 ); if ((cr == CR_NO_SUCH_DEVINST) || (cr == CR_NO_SUCH_VALUE)) { // // This is a phantom. Now get the DeviceInstanceId so we // can display this as output, then delete the phantom if requested. // if (CM_Get_Device_ID(DeviceInfoData.DevInst, DeviceInstanceId, SIZECHARS(DeviceInstanceId), 0) == CR_SUCCESS) { if (bDoRemove) { printf("DevNodePhantomCleaner: %s will be removed.\n", DeviceInstanceId); // // Call DIF_REMOVE to remove the device's hardware // and software registry keys. // if (SetupDiCallClassInstaller(DIF_REMOVE, DeviceInfoSet, &DeviceInfoData )) { DevicesRemoved++; } else { printf("CleanUp: Error 0x%X removing phantom\n", GetLastError); } } else { printf("CleanUp: %s would have been removed.\n", DeviceInstanceId); } } } } SetupDiDestroyDeviceInfoList(DeviceInfoSet); } } return DevicesRemoved; }
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Click the Debug menu, and then click Start Debugging.
How to build for Windows Server 2012 and Visual Studio 2012
To build for Windows Server 2012 and Microsoft Visual Studio 2012, follow these steps.DevNodeClean utility for this task. The following steps and the code example in step 7 are provided only for informational purposes.
Note We recommend that you use theÂ-
In Microsoft Visual Studio 2012, click New on the File menu, and then click Project.
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In the New Project dialog box, type Cleanup in the Name field, and then double-click Win32 Project.
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In the Win32 Application Wizard, click Next.
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Under Application type, click to select Console Application, and then click Finish.
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In Solution Explorer, expand Source Files, right-click Cleanup.cpp, and then click View Code.
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Locate the following code:
int _tmain(int argc, _TCHAR* argv[]) { return 0; }
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Replace the code that you found in step 6 with the following code.
//DevPhantomClnr.cpp : Defines the entry point for the console application. // #include "stdafx.h" /**************************************************************************************************/ /* */ /* Copyright (c) 2007 Microsoft Corporation. All Rights Reserved */ /* */ /**************************************************************************************************/ #pragma warning( disable : 4201 ) // nonstandard extension used : nameless strut/union #include <windows.h> #include <stdlib.h> #include <stdio.h> #include <stddef.h> #include <tchar.h> #include <setupapi.h> #include <cfgmgr32.h> #include <initguid.h> #include <devguid.h> #define SIZECHARS(x) (sizeof((x))/sizeof(TCHAR)) #define arraysize(p) (sizeof(p)/sizeof((p)[0])) CONST GUID *DiskClassesToClean[2] = { &GUID_DEVCLASS_DISKDRIVE, &GUID_DEVCLASS_VOLUME }; /**************************************************************************************************/ /* */ /* The user must be member of Administrator group and must have backup and restore permissions */ /* (SE_BACKUP_NAME and SE_RESTORE_NAME). No check for these is performed in this example. */ /* */ /**************************************************************************************************/ int __cdecl main( IN int ArgC, IN LPCWSTR pArgV[] ) { HDEVINFO DeviceInfoSet; SP_DEVINFO_DATA DeviceInfoData; ULONG DevicesRemoved = 0, i, MemberIndex, Status, Problem, ulClassesToCleanIdx; BOOL bDoRemove = TRUE; CONFIGRET cr; TCHAR DeviceInstanceId[MAX_DEVICE_ID_LEN]; OSVERSIONINFO osvi; const GUID ** ClassesToClean; // // Parse parameters. // for (i = 1; i < (ULONG)ArgC; i++) { // // Check for help. // if ( (lstrcmpi(pArgV[i], L"-?") == 0) || (lstrcmpi(pArgV[i], L"/?") == 0) ){ printf("\nDevNodePhantomCleaner will remove phantom storage device nodes from this machine.\n\n"); printf("Usage: nDevNodePhantomCleaner \n"); printf("\tWhere /n displays but does not remove the phantom devnodes.\n"); printf("\nBackup and Restore privileges are required to run this utility.\n"); return 0; } // // Check for -n, which means just list the devices that we would remove. // if ( (lstrcmpi(pArgV[i], L"-n") == 0) || (lstrcmpi(pArgV[i], L"/n") == 0) ) { bDoRemove = FALSE; } } // // Run only on Windows XP/2003 (version 5.1) or later. // ZeroMemory(&osvi, sizeof(OSVERSIONINFO)); osvi.dwOSVersionInfoSize = sizeof(OSVERSIONINFO); if (!GetVersionEx(&osvi)) { printf("DevNodePhantomCleaner: Unable to verify Windows version, exiting...\n"); return -1; } if ((osvi.dwMajorVersion == 5) && ((osvi.dwMinorVersion == 1) || (osvi.dwMinorVersion == 2))) { // 5.1 || 5.2 } else if (osvi.dwMajorVersion>=6) { //Nothing special on 6.x } else { printf("DevNodePhantomCleaner: This utility is designed to run on Windows XP/2003 and later\n"); return -1; } ClassesToClean = DiskClassesToClean; ulClassesToCleanIdx = arraysize(DiskClassesToClean); for (i=0; (i<ulClassesToCleanIdx) && (bDoRemove); i++) { DeviceInfoSet = SetupDiGetClassDevs(ClassesToClean[i], NULL, NULL, 0 ); if (INVALID_HANDLE_VALUE!=DeviceInfoSet) { DeviceInfoData.cbSize = sizeof(DeviceInfoData); MemberIndex = 0; while (SetupDiEnumDeviceInfo(DeviceInfoSet, MemberIndex++, &DeviceInfoData )) { // // Determine whether this device is a phantom. // cr = CM_Get_DevNode_Status(&Status, &Problem, DeviceInfoData.DevInst, 0 ); if ((cr == CR_NO_SUCH_DEVINST) || (cr == CR_NO_SUCH_VALUE)) { // // This is a phantom. Now get the DeviceInstanceId so we // can display this as output, then delete the phantom if requested. // if (CM_Get_Device_ID(DeviceInfoData.DevInst, DeviceInstanceId, SIZECHARS(DeviceInstanceId), 0) == CR_SUCCESS) { if (bDoRemove) { printf("DevNodePhantomCleaner: %ws will be removed.\n", DeviceInstanceId); // // Call DIF_REMOVE to remove the device's hardware // and software registry keys. // if (SetupDiCallClassInstaller(DIF_REMOVE, DeviceInfoSet, &DeviceInfoData )) { DevicesRemoved++; } else { printf("DevNodePhantomCleaner: Error 0x%x removing phantom\n", GetLastError()); } } else { printf("DevNodePhantomCleaner: %ws would have been removed.\n", DeviceInstanceId); } } } } SetupDiDestroyDeviceInfoList(DeviceInfoSet); } } return DevicesRemoved; }
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In Solution Explorer, right-click Cleanup, and then click Properties.
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Expand Configuration Properties, expand Linker, and then click Input.
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Select Additional Dependencies, click the down arrow, and then select Edit.
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In the Additional Dependencies dialog box, type setupapi.lib and cfgmgr32.lib.
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Click OK two times.
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Build the project.