Decompressing GZip file returns weird data

[Mattan360]

Hi!

I'm trying to decompress my GunZip files from the web using an WPF app, I get no errors, but then, when I open the files, I see randomly inserted "z" and my files aren't complete!

Here is my code:

string file = sr.ReadLine().Replace(".gz", "");
                SetInfo(Path.GetFileName(file));
                int size = Convert.ToInt32(sr.ReadLine());
                string inp = sr.ReadLine();
                int insize = Convert.ToInt32(inp);
                int pergo = insize;
                while (pergo > 256)
                    pergo /= 2;

                Uri uri = new Uri("http://mywebsite.com/data/" + file + ".gz");
                Stream stream = client.OpenRead(uri);

                byte[] data = new byte[size];
                stream.Read(data, 0, data.Length);

                MemoryStream ms = new MemoryStream(data);
                ms.Seek(0, SeekOrigin.Begin);

                GZipStream gzipstream = new GZipStream(ms, CompressionMode.Decompress);
                string path = installPath + file;
                FileStream fstream = File.Create(path);
                while (insize > 0)
                {
                    if (pergo > insize)
                        pergo = insize;

                    byte[] decompressed = new byte[pergo];
                    gzipstream.Read(decompressed, 0, pergo);
                    fstream.Write(decompressed, 0, decompressed.Length);
                    insize -= pergo;
                }

                gzipstream.Close();
                gzipstream.Dispose();
                fstream.Close();
                fstream.Dispose();
                stream.Close();
                stream.Dispose();

My files aren't corrupted, I can still open them with IZark, and they work. (The files on the server not the downloaded ones)
Please tell what I'm doing wrong??