SQL Exception Generated By Server

HI all,

if this issue has been solved, please provide me the post, or I've put this issue in a wrong category please let me know.

The following is my code:

DateTime dtBFWNow = DateTime.Today;

String dtBFW_range1 = dtBFWNow.AddDays(-7).ToShortDateString();

String dtBFW_range2 = dtBFWNow.AddDays(3).ToShortDateString();

SqlDataSource1.SelectCommand = "SELECT * FROM [MORTGAGE] WHERE ([BringForwardDate] is not null) and ([BringForwardDate]>= '" + dtBFW_range1 + "' and [BringForwardDate] <= '" + dtBFW_range2 + "')";

lblHeader.Text = "Bring Forward Reminders Due From '" + dtBFW_range1 + "' To '" + dtBFW_range2 + "'";

lblHeader.ForeColor = System.Drawing.Color.FromName("#000000");

GridView1.DataBind();

When I compiled, the following exception occurred:

The conversion of a char data type to a datetime data type resulted in an out-of-range datetime value.

and the exception points right at the line: GridView1.DataBind() 

I use the webhost4life as my server provider.  My codes run fine with the server.  I mean I uploaded my program to the server, set up and run the program online, everything is fine. 

But on my PC it gives me the above exception.  I can't compile my code.  There must be some sort of setting somewhere in my PC that can't handle the exception.

Please help.

Regards.

Joey.