File and folder synchronization, on FileSystemItem and FileSystemItem-derived objects, such as AbstractFile or AbstractFolder objects and their derivatives 

Full Windows Vista support

Three new "Quick" classes provide static methods that let you perform FTP, Tar, and GZip operations with a single line of code: QuickFtp, QuickTar, and QuickGZip. These new classes accompany and complement the currently available QuickZip and QuickCompression classes.

Xceed FTP for .NET Compact Framework

The only library to provide WinZip 12 compatibility, supporting the LZMA algorithm for improved compression in certain situations. Note: Zip files using WinZip 12’s special JPEG recompression feature are not supported. (New in version 4.1)

UTF-8 character encoding is available in headers for improved support of international characters in filenames and comments. (New in version 4.1)

Support for the Zip64 zip file format 

Support for BZip2 compression algorithm

Support for the PPMd compression algorithm, for producing the most compressed output possible, especially with text and XML files

Support for extra headers containing detailed time-stamp information in both PKWARE and Info-Zip formats (last modified, last accessed and creation) and Unicode file names (for international characters). 

Create new zip files or update existing zip files on disk or in memory 

Read, write and update zip files split into multiple parts 

Read, write and update zip files that span multiple disks 

Create powerful fully customized self-extracting zip files 

Supports the new Deflate64™ compression method 

List contents of a zip file with complete file specifications 

Compress or decompress any .NET stream 

Supports encryption and decryption of .NET streams using compatible encryption.

Compress and decompress byte arrays completely in memory 

Copy, move, rename, delete and change attributes of files and folders in a zip file, on disk, in memory or in isolated storage 

Zip password encryption 

One-line shortcut classes for basic zip file and compression operations 

Fully extensible classes so you can customize the library’s functionality as needed 

Information-rich status report events with percentages, byte and file counts 

Programmable filter system to limit processing to specific files or folders, with built-in filters for file attribute, size, date timestamp and filenames. Create your own custom filters as needed.

Efficiently creates zip files by allowing developers to decided whether folder entries should be written to the archive, which reduces its size. (New in version 5.1/4.3)

Can create archives using the Deflate format without compression, for full compatibily with Xceed Real-Time Zip and generally improved flexibility. (New in version 5.1/4.3)

Tar and GZip for maximum compatibility between your applications and the data they need to work with 

Handle Tar and GZip files as easily as if they were regular files and folders 

Full read/write compatibility with USTAR format Tar archives 

Read compatibility with GNU Tar archives as long as archive entries do not use the header extensions of this format

Zip encryption on a per-file basis (password protection only in .NET CF version) 

Recursively zip or unzip entire directories and their contents 

Control the path information stored in the zip file for each file or folder 

Zip or unzip only files newer than those already in the zip file or destination folder 

Overwrite files only in certain conditions 

Split zip file can use the Pkware or Xceed naming convention for each zip file part or create your own custom naming convention 

Split zip file parts can be written to different folders 

Triggers only the events your application subscribes to for increased performance 

Get and set individual file comments or the global zip file comment 

Supports different encryption passwords for each file 

Controllable compression levels and methods 

Ability to preview which files will end up being processed 

Process system and hidden files, overwrite read-only files 

Supports the GZip, Zlib, Info-Zip, Java and proprietary compression formats that include embedded checksums to ensure data integrity 

True .NET pass-through stream object that can automatically compress or decompress any other type of .NET stream's data 

Calculate CRC-32 and Adler-32 checksums on streams or byte arrays

Create new self-extracting zip files or transform already existing zip files into self-extracting zip files 

Self-extracting zip files can span multiple disks 

Creates 32-bit self-extracting zip files that work on all Windows 95, 98, ME, NT, 2000, and XP operating systems, or 16-bit self-extracting zip files that work on Windows 3.x as well 

Update and reconfigure an existing self-extracting zip file 

Create self-extracting Zip files for the traditional PKZIP 2.04g compression method. Also supports the Deflate64™, BZip2, and BWT methods.

Create self-extracting zip files that support AES encryption. (Not available in CF version)

Supports the Zip64 zip file format allowing the creation of Zip files which can contain a practically unlimited number of archived files. Note: Due to limitations in the Windows operating system, creating or using self-extracting Zip files larger than 2 GB is not recommended.

Customizable introduction message and dialog box titles 

Display a license agreement with configurable accept and refuse buttons 

Customize all other messages, prompts and button captions 

Customize the self-extracting zip file's application icon (not available in .NET CF version) 

Set the default unzipping folder 

Allow user to select an alternate unzipping folder 

Request a password whenever an encrypted file is encountered 

The user can enter the decryption password or skip the file if they don't have the password for the file 

Display a text file after successfully unzipping files 

Customizable overwrite behavior with dialog box offering the user various overwrite options 

Display unzipping status 

User interaction and dialogs can be selectively shut off for quiet operation 

Execute one or more applications (optionally with parameters) or open documents after successfully unzipping files 

Copy one or more files from one location to another after unzipping 

Register DLLs (or other libraries) on the system after unzipping 

Add or change key values in the registry after unzipping 

Create self-extracting zip files with a built-in decryption password. This prevents users from using compression utilities to unzip the files, forcing users to view your custom introduction, license agreement or warning messages 

Create program groups and insert items into program groups 

Associate filename extensions with applications 

Allows 3rd-party install or setup programs (and their data files) to be unzipped into a temporary folder, executed, and then deleted upon completion 

Custom paths, filenames, strings and prompts are parsed, allowing you to insert strings such as the current folder, windows and windows system directories, the temporary folder, and more