hello,I have been battling with an upgrade issue for two days. The upgrade gets about half way done and then the following error is generated. Does anyone know what this is?

Server Error in '/' Application.System.ApplicationException: Unknown block type 6 at ICSharpCode.SharpZipLib.Zip.Compression.Inflater.Decode() at ICSharpCode.SharpZipLib.Zip.Compression.Inflater.Inflate(Byte[] buf, Int32 offset, Int32 len) at ICSharpCode.SharpZipLib.Zip.Compression.Streams.InflaterInputStream.Read(Byte[] b, Int32 off, Int32 len)Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: ICSharpCode.SharpZipLib.ZipException: System.ApplicationException: Unknown block type 6 at ICSharpCode.SharpZipLib.Zip.Compression.Inflater.Decode() at ICSharpCode.SharpZipLib.Zip.Compression.Inflater.Inflate(Byte[] buf, Int32 offset, Int32 len) at ICSharpCode.SharpZipLib.Zip.Compression.Streams.InflaterInputStream.Read(Byte[] b, Int32 off, Int32 len)Source Error: Line 261: Upgrade.Upgrade.InstallPackages("Container", true);Line 262: Upgrade.Upgrade.InstallPackages("Language", true);Line 263: Upgrade.Upgrade.InstallPackages("Provider", true);Line 264: Upgrade.Upgrade.InstallPackages("AuthSystem", true);Line 265: Upgrade.Upgrade.InstallPackages("Package", true);Source File: d:\websites\www.krisis.ca\dnn\Install\Install.aspx.cs Line: 263 Stack Trace: [ZipException: System.ApplicationException: Unknown block type 6 at ICSharpCode.SharpZipLib.Zip.Compression.Inflater.Decode() at ICSharpCode.SharpZipLib.Zip.Compression.Inflater.Inflate(Byte[] buf, Int32 offset, Int32 len) at ICSharpCode.SharpZipLib.Zip.Compression.Streams.InflaterInputStream.Read(Byte[] b, Int32 off, Int32 len)] ICSharpCode.SharpZipLib.Zip.Compression.Streams.InflaterInputStream.Read(Byte[] b, Int32 off, Int32 len) +423 ICSharpCode.SharpZipLib.Zip.ZipInputStream.Read(Byte[] b, Int32 off, Int32 len) +91 DotNetNuke.Services.Installer.Util.StreamToStream(Stream sourceStream, Stream destStream) +77 DotNetNuke.Services.Installer.Util.WriteStream(Stream sourceStream, String destFileName) +160 DotNetNuke.Services.Installer.InstallFile.ReadZip(ZipInputStream unzip, ZipEntry entry) +50 DotNetNuke.Services.Installer.InstallerInfo.ReadZipStream(Stream inputStream, Boolean isEmbeddedZip) +182 DotNetNuke.Services.Installer.Installer..ctor(Stream inputStream, String physicalSitePath, Boolean loadManifest, Boolean deleteTemp) +297 DotNetNuke.Services.Upgrade.Upgrade.InstallPackage(String file, String packageType, Boolean writeFeedback) +405 DotNetNuke.Services.Upgrade.Upgrade.InstallPackages(String packageType, Boolean writeFeedback) +373 DotNetNuke.Services.Install.Install.UpgradeApplication() in d:\websites\www.krisis.ca\dnn\Install\Install.aspx.cs:263 DotNetNuke.Services.Install.Install.OnLoad(EventArgs e) in d:\websites\www.krisis.ca\dnn\Install\Install.aspx.cs:492 System.Web.UI.Control.LoadRecursive() +71 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +3064

EDIT # 1:

I am still fighting with this. I tried several upgrades and now i am getting different errors, is there another way to upgrade other than copying the files over and then running the upgrade process?Looking for any other suggestions here.