C#

string MOMO1, MOMO2;
string[] WI;
string ALL;
private void Actualizar(object s, EventArgs e)
{
    ALL = SB.ToString().Trim();
    WI = ALL.Split(',');
    ALL = WI[2].ToString().Trim();
    MOMO1 = ALL.Replace("+", "").Replace("g", "").Replace("ST", "").Replace("GS", "").Replace("US", "");
    if (MOMO1 != "")
    {
        MOMO2 = MOMO1;
    }
    lblMSG.Font = new Font("Ariel", 48, FontStyle.Bold);
    lblMSG.Text = MOMO2;
    Check_Weight();
    GC.Collect();  // <-- is it OK ?
}

1. open the saved .gz file in the standard way

2. create a new file to hold the un-gzipped .xml whose name is the same as the GZip file, with the .gz extension replaced with .xml.

// compressedstuff.gz => compressedstuff.xml

3. create a new GZip compression stream with Decompress option

4. copy the Gzip compression stream into the new file

5. re-create the "object" in the standard way from file using WCF Serializer

using System.Runtime.Serialization;
using System.IO;
using System.IO.Compression;

public static SomeClass GZToObject(string gzFilePath)
{ 
    DataContractSerializer serializer = new DataContractSerializer(typeof(SomeClass));

    SomeClass someClassInstance = null;
    
    FileInfo fileToDecompress = new FileInfo(gzFilePath);
    
    using (MemoryStream xmlStream = new MemoryStream())
    {
        using (GZipStream deCompStream = new GZipStream(File.Open(gzFilePath, FileMode.Open), CompressionMode.Decompress, true))
        {
            deCompStream .CopyTo(xmlStream);
            deCompStream .Close(); // using 'Close here fixes a common problem with GZipStream
            
            // set breakpoint here: xmlStream appears to be valid de-compressed XML
            
            // error here: unexpected end of file
            someClassInstance = (SomeClass) serializer.ReadObject(xmlStream);
        }
    }
    
    return someClassInstance;
}