Private Sub ThisWorkbook_Startup(ByVal sender As Object, ByVal e As System.EventArgs) _
    Handles Me.Startup

    MessageBox.Show("The workbook is deployed successfully.")
End Sub

private void ThisWorkbook_Startup(object sender, System.EventArgs e)
{
    MessageBox.Show("The workbook is deployed successfully.");
}

Imports Microsoft.VisualStudio.Tools.Applications.Runtime

using Microsoft.VisualStudio.Tools.Applications.Runtime;

Public Overrides Sub Install(ByVal stateSaver As System.Collections.IDictionary)
    UpdateApplicationManifest()
    MyBase.Install(stateSaver)
End Sub

Private Sub UpdateApplicationManifest()

    ' Get the parameters passed to the task.
    Dim targetDir As String = Me.Context.Parameters("targetdir")
    Dim documentName As String = Me.Context.Parameters("documentname")
    Dim assemblyName As String = Me.Context.Parameters("assemblyname")

    ' Get the application manifest from the document.
    Dim documentPath As String = System.IO.Path.Combine(targetDir, documentname)
    Dim serverDocument1 As ServerDocument = New ServerDocument(documentPath, _
            System.IO.FileAccess.ReadWrite)

    Try
        Dim appManifest1 As AppManifest = serverDocument1.AppManifest
        Dim assemblyPath As String = System.IO.Path.Combine(targetDir, assemblyName)
        appManifest1.Dependency.AssemblyPath = assemblyPath
        serverDocument1.Save()

    Finally
        If Not serverDocument1 Is Nothing Then
            serverDocument1.Close()
        End If
    End Try
End Sub

// Override the Install method to update the customization location
// in the application manifest.
public override void Install(System.Collections.IDictionary stateSaver)
{
    UpdateApplicationManifest();
    base.Install(stateSaver);
}

// Update the application manifest according to the the install location.
private void UpdateApplicationManifest()
{
    // Get the parameters passed to the task.
    string targetDir = this.Context.Parameters["targetdir"];
    string documentName = this.Context.Parameters["documentname"];
    string assemblyName = this.Context.Parameters["assemblyname"];

    // Get the application manifest from the document.
    string documentPath = System.IO.Path.Combine(targetDir, documentName);
    ServerDocument serverDocument1 = new ServerDocument(documentPath,
        System.IO.FileAccess.ReadWrite);

    try
    {
        AppManifest appManifest1 = serverDocument1.AppManifest;
        string assemblyPath = System.IO.Path.Combine(targetDir, assemblyName);
        appManifest1.Dependency.AssemblyPath = assemblyPath;
        serverDocument1.Save();
    }
    finally
    {
        if (serverDocument1 != null)
        {
            serverDocument1.Close();
        }
    }
}