SPList Object is null After back/restore SITE

Question

after a bakup/ restore of SPWEB, if I try to Get a SPLIST by Server object Model code, it returns me

 public bool OnNotification(SPAlertHandlerParams ahp)
 {
  SPSecurity.RunWithElevatedPrivileges(delegate()
            {
                using (SPSite site = new SPSite(ahp.siteUrl))
                {
                    using (SPWeb web = site.OpenWeb())
                    {

                        SPList lookupList = web.Lists[new Guid(ahp.a.ListID.ToString())];
                        //list = web.Lists[ahp.a.ListID];
                    }
                }
            });

List does not exist. The page you selected contains a list that does not exist. It may have been deleted by another user.

If I try to get the same list using COM, the result is success:

 string siteUrl = "http://mysite/";
            SP.ClientContext clientContext = new SP.ClientContext(siteUrl);
            clientContext.Credentials = new NetworkCredential("user", "pass", "domain");
            SP.List oList = clientContext.Web.Lists.GetByTitle("mylist");

            clientContext.Load(oList);
            clientContext.ExecuteQuery();

Answer 1

Can you try using below?

var list = web.TryGetList("Title");

I think the problem with your SSOM code is quite obvious. Let me know if snippet above works.