How To Detect Safe Mode Startup with Visual Basic (291664)

SUMMARY

For some applications, it may be useful to detect if the local system was started in Safe Mode in order to run appropriately in this mode or to avoid running in Safe Mode. This article describes how to use a Win32 application programming interface (API) to determine the startup mode of the local system.

MORE INFORMATION

You can use the GetSystemMetrics function with the SM_CLEANBOOT index specified to detect the startup mode of the system. The SM_CLEANBOOT index returns one of three values, based on how the system was started:

Return Value	Meaning
0	Normal Boot
1	Safe Mode
2	Safe Mode with Networking

Step-by-Step Example

The following Visual Basic code demonstrates how to detect Safe Mode:

Start a new Visual Basic standard EXE project. Form1 is created by default.
Add a new command button (Command1) to Form1.

Paste the following code into the code window of Form1:

Private Declare Function GetSystemMetrics Lib "user32" _
   (ByVal nIndex As Long) As Long

Const SM_CLEANBOOT& = 67

Private Sub Command1_Click()
    Dim result As Long
    
    result = GetSystemMetrics(SM_CLEANBOOT)
    
    Select Case result
        Case 0
            MsgBox "System started in normal mode."
        Case 1
            MsgBox "System started in safe mode."
        Case 2
            MsgBox "System started in safe mode with networking."
        Case Else
            MsgBox "Unknown value returned from GetSystemMetrics."
    End Select
End Sub

Click Run, or press the F5 key, to run the project.
Click Command1. Notice that a message appears that reflects the startup mode of your system.

REFERENCES

For additional information using the API from Visual Basic, click the article number below to view the article in the Microsoft Knowledge Base:

190000 How To Get Started Programming with the Windows API (LONG)

The MSDN Platform SDK Help for GetSystemMetrics

The Visual Basic Programmer's Guide