String url = "window.open('ProjectCompleteDetails?ProjectId=" + projectid + "','_newtab');";
ScriptManager.RegisterStartupScript(this, this.GetType(), "OpenWindow", "window.open('url','_newtab');", true);
or
ScriptManager.RegisterStartupScript(UpdatePanel2, UpdatePanel2.GetType(), "OpenWindow", window.open('url','_newtab');", true);
Will open in new tab but same tab again and again and not in other new tab ?????? Why
