Bound Access database update and fill problem

[NormanB]

I have a bound Access database which contains tables "Recipes", "Ingredient s" and "Units". A linked table "Recipe ingredients" holds id references to each of these tables.

My problem occurs when importing a new recipe from a text file. I create the reipe first and call the adapter update for the recipes table and then refill it. Then I create an entry in the recipe_ingredie nts table which I also update and try to refill. However when I then call the recipe_ingredie ntsAdapter.Fill I get a "Object reference not set to an instance of an object" error which suggests a null value somewhere.

I have checked that all the data is valid. Also if I use Access to open the modified database file after the updates it is perfectly happy - so is my own programme if I re-run it using the modified database.

Any ideas where the error message may be coming from? Attached are code snippets from the relevant routines.

Thanks

    private int ImportRecipe(string rcp)
    {          

        {
        ....... Some text parsing of string rcp to extract the data values
                and create an ArrayList (AllIngs) of Ingredient strings
        }

        // Create a new recipe row
        recipesDataSet.RecipesDataTable table = (recipesDataSet.RecipesDataTable)recipesDataSet.Tables["Recipes"];
        recipesDataSet.RecipesRow row = table.AddRecipesRow(title
            ,foodrow
            ,veggy
            ,Preptime
            ,nserve
            ,ncal
            ,nutrition
            ,instructions
            ,notes
            ,bookrow
            ,wheat
            ,dairy
            ,utensils
            ,page);

        recipesTableAdapter.Update(table);
        recipesTableAdapter.Fill(recipesDataSet.Recipes);

        // Now we have a new recipe id we can update other related table
        int newid = (int)table.Rows[table.Count - 1]["RecipeID"];
        UpdateRecipeIngredientsTable(ref AllIngs, newid);
        return newid;
    }

    private void UpdateRecipeIngredientsTable(ref ArrayList list, int recid)
    {
        recipesDataSet.Recipe_IngredientsDataTable table = (recipesDataSet.Recipe_IngredientsDataTable)recipesDataSet.Tables["Recipe Ingredients"];
        int id = 0;
        foreach (Ingredient ing in list) {
            recipesDataSet.Recipe_IngredientsRow drow = (recipesDataSet.Recipe_IngredientsRow)table.NewRow();
            drow["RecipeID"] = recid;
            drow["IngredientID"] = ing.ingID;
            drow["Quantity"] = ing.quantity.ToString();
            drow["UnitID"] = ing.unitID;
            drow["Order"] = ++id;
            table.AddRecipe_IngredientsRow(drow);
        }
        recipe_IngredientsTableAdapter.Update(table);
        try {
            recipe_IngredientsTableAdapter.Fill(recipesDataSet.Recipe_Ingredients);
        }
        catch (Exception ex) {
            MessageBox.Show(ex.Message);
        }
    }