Double extensions when compressing file with c# (*.GZip)

[Charp]

I have an application that saves data to a MS Access database and then compresses it. The annoyance here is that I get a double extension on my zip folder. (*.accdb.gz).

I have come up with an alternative but it causes the compressed file to not get any extension at all. The problem is that I name both the folder and the file in the same line and I'm wondering if there's a way to seperate them.

private void CompressFile(string DirectoryPath)
{
    DirectoryInfo di = new DirectoryInfo(DirectoryPath);
    FileInfo fi = new FileInfo(DirectoryPath);

    using (FileStream inFile = fi.OpenRead())
    {
        using (FileStream outFile = File.Create(fi.Directory + "\\(" + currTime.ToShortDateString() + ")RSDB.accdb.gz"))
        {
            using (GZipStream Compress = new GZipStream(outFile, CompressionMode.Compress))
            {
                inFile.CopyTo(Compress);
            }
        } 
    }  
}

This is the line that sets the name:

using (FileStream outFile = File.Create(fi.Directory + "\\(" + currTime.ToShortDateString() + ")RSDB.accdb.gz"))

Taking away the first extension leaves the file without any extension at all.