What is wrong with this...

' define and get the Customers Master
Dim cmdSQL_C As New SqlCommand("Select Top 1 * from Customers where CustomerID = @CustomerID")
cmdSQL_C.Connection = conSQL
cmdSQL_C.Parameters.Add("@CustomerID", System.Data.SqlDbType.Int)
cmdSQL_C.Parameters("@CustomerID").Value = TextBox3.Text 'has a valid key value
conSQL.Open()
Rdr = cmdSQL_C.ExecuteReader()
Rdr.Read()

At the .ExecuteReader I get the error :

An unhandled exception of type 'System.FormatException' occurred in system.data.dll

Additional information: Input string was not in a correct format


The key to Customers is nchar(5).

When I use this same set of code for a key that numeric .. all is fine... What's up???

gollnick