Hi Mayank,
    The best solution I can suggest is that as you remove the TabPages from the Tab Control, keep the removed pages in the list so that you can get them later...

Please go through the following example this will give you the exact idea I am talking about:

private List<TabPage> removedPages = new List<TabPage>();

    private void EnablePage(TabPage page, bool enable) {
        if (enable) {
            tabControl1.TabPages.Add(page);
            removedPages.Remove(page);
        }
        else {
            tabControl1.TabPages.Remove(page);
            removedPages.Add(page);
        }
    }

    protected override void OnFormClosed(FormClosedEventArgs e) {
        foreach (var page in removedPages) page.Dispose();
        base.OnFormClosed(e);
    }