The compressed data returned by the XceedCompression object (Xceed Zip ActiveX) or the XceedCompressedStream class (Xceed Streaming Compression for .NET and Xceed Zip for .NET Compact Framework) contains a custom header, consisting of a single byte at the beginning, and four bytes (An Adler-32 checksum) at the end.
That is why ZLib is not able to uncompress the data correctly.
For ZLib compatiblity, use the Xceed Streaming Compression Library or the ZLibCompressedStream class of Xceed Streaming Compression for .NET or Xceed Zip for .NET Compact Framework.
Imported from legacy forums. Posted by Xceed admin (had 1066 views)