My site was working a week ago, and now suddenly it isn't.

I can't get it to read the cookies I am saving. Maybe you can help.

This is how I am writing the cookie:

Dim cookie As HttpCookie = Request.Cookies("EmployeeID")
If Request.Cookies("EmployeeID") Is Nothing Then
Response.Cookies("EmployeeID").Value = Request.QueryString("employeeid")
Response.Cookies("EmployeeID").Expires = DateTime.Now.AddDays(7)
End If

And now I can't get the site to read the cookie for use in datagrids etc.

I can't see anything immediatly wrong with what you're doing. I personally use the Cookies.Add method to register new cookies so you could try it instead:

(Writing)

Page.Response.Cookies.Add(new System.Web.HttpCookie("My Cookie","My Value"));

(Reading)

if (Page.Request.Cookies["My Cookie"] != null)
  myVariable = Page.Request.Cookies["My Cookie"].Value; // myVariable = "My Value" 

Now I am able to see the cookie on the page I am writing it, but as soon as I redirect to the next page the cookie seems to disappear.

Response.Redirect("/Admin/Default.aspx?id=" & Request.Cookies("employeeid").Value)

takes me to the page with the id set to a number, but once on that page I cannot read the value from the cookie itself

Hi,

Based on my understandings, you create the cookies in the first page, and then transfer to another page named second page. In the second page you get the cookie's value. But if the second page redirect to the third page, you can't get the cookie's value in the third page. If I understood the issue, I suggest to run the following code which run well under my environment.

First.aspx.cs

        Page.Response.Cookies.Add(New System.Web.HttpCookie("employeeid", "My Value"))
        Response.Redirect("Second.aspx")

Second.aspx.cs

       Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        Dim myVariable As String = Page.Request.Cookies("employeeid").Value
        Response.Write(myVariable)

      End Sub

      Protected Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs) Handles Button1.Click
        Response.Redirect("Third.aspx?id=" & Request.Cookies("employeeid").Value)
      End Sub

Third.aspx.cs

       Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

        Dim readFcookie As String = Page.Request.Cookies("employeeid").Value 'read from cookie
        Response.Write("read from cookie " & readFcookie)
        Response.Write("<br/>")
        Dim readFget As String = Request.QueryString("id").ToString() 'read from cookie
        Response.Write("read from get " & readFget)

    End Sub

If it still not work, please post some relative code for here. I understand that this may be a lot of information to ask for at one time. However, by collecting this information now, it will help us move more quickly toward a solution.

 If I misunderstood the issue, please inform of me.