When we install any application, registry of system keeps the unisntall command in the
Property : UninstallString
So we will get the this cammnad from registry and save in the batch file and execute the
batch file.
Vb.net code for this as follow:

Imports
Microsoft.Win32
Imports
System.IO
Module
 
Module1Dim MyAppStr As String = "MySetup"
 
Dim RegistryPath As String
 
 
 
Dim RegistryKeyObj As RegistryKeyDim CurrentRegKeyObj As RegistryKeyDim IsMyAppBool As Boolean = False
RegistryPath =
Dim ProcessInfoObj As ProcessStartInfoDim UnInstallCmdStr As String = String.EmptyDim ProcessObj As New ProcessDim TempBachFile As StreamWriterSub Main()"SOFTWARE\MICROSOFT\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Products"
RegistryKeyObj = Registry.LocalMachine.OpenSubKey(RegistryPath)
 
Try
 
CurrentRegKeyObj = RegistryKeyObj.OpenSubKey(ApplicationObj).OpenSubKey(
 
For Each ApplicationObj As String In RegistryKeyObj.GetSubKeyNames"InstallProperties")If Not CurrentRegKeyObj Is Nothing Then
 
If String.Compare(CurrentRegKeyObj.GetValue("DisplayName").ToString, MyAppStr) = 0 Then
UnInstallCmdStr = CurrentRegKeyObj.GetValue(
TempBachFile =
TempBachFile.WriteLine(UnInstallCmdStr)
TempBachFile.Close()
ProcessInfoObj =
ProcessInfoObj.RedirectStandardOutput =
"UninstallString").ToStringNew StreamWriter("Uninstall.bat")New ProcessStartInfo("Uninstall.bat")True
ProcessInfoObj.UseShellExecute =
False
ProcessInfoObj.CreateNoWindow =
False
ProcessObj.StartInfo = ProcessInfoObj
ProcessObj.Start()
ProcessObj.WaitForExit()
IsMyAppBool =
True
 
Exit For
 
End If
 
End If
 
Next
 
If IsMyAppBool = False Then
Console.WriteLine(
 
"Application : " & MyAppStr & " had not installed in the system.")End If
 
Console.WriteLine(ex.Message)
 
Catch ex As ExceptionEnd Try
Console.ReadKey()
 
End
End Sub Module