How to Remedy Error System.UnauthorizedAccessException in My Console App?

Question

I've programmed a console app using C#.

When I run the console app I receive the error noted above. My programming logic is as follows:

class Program
{
    static void Main(string[] args)
    {
        string path = @"\\mypath\\mydirectory";
        DirectoryInfo di = new DirectoryInfo(path);
        FileInfo[] files = di.GetFiles();
        string year = DateTime.Now.Year.ToString();
        string month = DateTime.Now.Month.ToString("d2");
        string day = DateTime.Now.Day.ToString("d2");
        string feedVersion;
        string manifestFileName = "MyFile_" + year + month + day + ".manifest";
        string manifestDest = di + manifestFileName;
        string manifestHeader = "FileName|Version|Line_Count|SHA256HASH";
        StreamWriter oFile = new StreamWriter(manifestDest);
        FileStream uploadFile = File.OpenWrite(manifestFileName);

        using (SHA256 mySHA256 = SHA256.Create())
        {
            oFile.WriteLine(manifestHeader);
            foreach (FileInfo finfo in files)
            {
                if (finfo.Name.Contains("labdata"))
                {
                    feedVersion = "200";
                }
                else if (finfo.Name.Contains("pharm"))
                {
                    feedVersion = "200";
                }
                else if (finfo.Name.Contains("claim"))
                {
                    feedVersion = "200";
                }
                else if (finfo.Name.Contains("enrollment"))
                {
                    feedVersion = "220";
                }
                else if (finfo.Name.Contains("member"))
                {
                    feedVersion = "202";
                }
                else if (finfo.Name.Contains("provider"))
                {
                    feedVersion = "220";
                }
                else if (finfo.Name.Contains("hierarchy"))
                {
                    feedVersion = "200";
                }
                else if (finfo.Name.Contains("member*attribution"))
                {
                    feedVersion = "200";
                }
                else
                {
                    feedVersion = "NA";
                }
                using (uploadFile)
                {
                    try
                    {
                        var lineCount = File.ReadAllLines(di.ToString());
                        var fileName = Path.GetFileName(di.ToString());
                        byte[] hashValue = mySHA256.ComputeHash(uploadFile);
                        //Console.Write($"{finfo.Name}: ");
                        oFile.WriteLine(fileName.ToString() + "|" + feedVersion.ToString() + "|" + lineCount.ToString() + "|" + hashValue);
                    }
                    catch (Exception ex)
                    {
                        Console.WriteLine(ex.Message);
                    }
                }
                oFile.Close();
                oFile.Dispose();

            }

        }

        Console.WriteLine("Success");
    }
    public static void PrintByteArray(byte[] array)
    {
        for (int i = 0; i < array.Length; i++)
        {
            Console.Write($"{array[i]:X2}");
            if ((i % 4) == 3) Console.Write(" ");
        }
        Console.WriteLine();
    }

}

What modifications are needed to ensure that the file can be created in the directory as specified and that it contains all the needed information in it?