Zen's yEnc FAQ
0. What is it
1. Windows programs
2. Macintosh
3. Unix/Linux
4. Others O/Ses
5. Q and A
6. Posting program
7. Alternative/older methods

What is it?
yEnc is an Usenet binary transport format, like UUEncoding, Base64 or Binhex, but with much more efficiency.
(All binaries must be encoded before to go on Usenet, because Usenet doesn't support raw binaries.)
UUencode adds 40% overhead, yEnc adds only 1%-5%.

Test example: test.rar
Size in bytes
Original binary:
0 %
+ 40 %
+ 38 %
+ 37 %
+ 4 %

Downloads and uploads are quicker due to the reduced overhead.
Also, yEnc has error checking built-in. It will tell you right away if a file has been corrupted, or if you are using a smart newsreader and multiple newsservers it will get a good copy of the bad segment from another source.
And the files can be decoded out of sequence. Plus, even if segments overlap or are of different sizes they will decode correctly, because yEnc binaries contain positioning information.
The provider can keep the binaries longer as they take less space.
People who are on metered access can give and get more, or save money.
Even those with dialup modems and compression enabled will save time and bandwidth.

Main yEnc site: http://www.yenc.org

absmc yEnc FAQ: http://www.oocities.com/altbinariessoundsmusicclassical/yenc.html
Ozum basic FAQ: http://www.ozinsight.com/yencfaq.html
Some yEnc facts: http://www.roadwarriorcomputers.com/yenc/yencfacts.html
yEnc Myths and Misconceptions: http://www.exit109.com/~jeremy/news/yencmyths.html

Under Windows, yEnc is supported by the following programs (and more):

Xnews: http://xnews.newsguy.com
Super Gravity: http://gravity.tbates.org
MicroPlanet Gravity, with source code: http://sourceforge.net/projects/mpgravity
GrabIt: http://www.shemes.com/grabit
BNR2: http://www.co.jyu.fi/~ap/bnr.html
MesNews: http://mesnews.net/index-gb.php
NewsGreed - simple java binary downloader, with source: http://www.oocities.com/newsgreed
NewZMiner: http://www.newzminer.com
Pan, Windows' port: http://pan.rebelbase.com
Power-Grab 2002: http://cosmicwolf.com
WinVN, with source code: http://www.execpc.com/~mspankus
XanaNews, with source code: http://www.wilsonc.demon.co.uk/d7xananews.htm
AllNews, under development (also Win3.1 version): http://members.tripod.com/~MikeRead
40Tude Dialog: http://www.40tude.com/dialog

Agent: http://www.forteinc.com - trial
ASP1-A3 for pictures: http://www.wmhsoft.com/ASP1-A3/ - trial
AutoPix for pictures only: http://www.kbrowning.com - free download
Binary Boy Pro: http://www.binaryboy.com - $30
Binary News Assistant: http://www.nijico.com - pre-release
Binary Vortex for pictures only: http://www.binaryvortex.com - free download
Express NewsPictures for binaries: http://www.express-soft.com - free download
Giganews: http://uwekel.bei.t-online.de/giganews.htm - shareware
Newsbin Pro: http://www.newsbin.com - free trial
Aaron's NewsBin: http://www.surfwarelabs.com - 10-day trial
Newsleecher: http://www.newsleecher.com - free trial
News Rover: http://www.newsrover.com - free demo
NewsPro: http://www.usenetopia.com/ - 30-day trial
NewsReactor: http://www.daansystems.com/newsreactor - shareware
NewsShark: http://www.wmhsoft.com/NewsShark - trial
NewzTrix: http://www.opalsoftware.co.uk - free to try
Nomad News: http://www.nomadnews.com - trial
NovusNews: http://www.novusnews.com - pre-release
Ozum Newsreader and Autoposter: http://www.ozinsight.com - 30 days trial
PictureAgent : http://www.pictureagent.com - free for 10 days
PixNewsPro: http://www.techsono.com/pixnewspro - free download
Pluckit, binary searcher: http://www.pluckit.com - demo
QuadSucker/News, for images: http://www.quadsucker.com - free download
SBNews: http://www.newsrobot.com/sbnews - shareware
Tifny: http://www.tifny.com - trial
Zeonews: http://www.zeonews.com - discontinued

Japanese HyperNewsReader: http://www.fan.hi-ho.ne.jp/treasure - free download
Japanese News Extractor: http://homepage3.nifty.com/~foo/ - free download
Japanese XacRett: http://www.kmonos.net/lib/xacrett.ja.html
Japanese Archon, Susie plug-in: http://www.vector.co.jp/soft/win95/util/se238177.html

Note that some of the commercial/ads-supported newsreaders may contain some form of spyware/"phoning home"-ware. Be sure to have a good antivirus and a good firewall installed and to read the software manual's fine print. Visit http://www.anti-spyware-review.toptenreviews.com for more tools.

Non-yEnc newsreaders:
- yProxy: http://www.brawnylads.com/yproxy - freeware up to v1.3, now $15.
yProxy transparently enables any binary newsreader to support yEnc decoding for downloading binary attachments.
Works with Outlook Express, Netscape, Free Agent, etc.
- Fidolook: http://www.fidolook.org/ - free
Fidolook is a freeware extension for Microsoft Outlook Express.

If you want to do it manually: save as raw binary and use an external decoder on the saved file:
- yDec v1: http://www.yenc.org/ydec1.zip from http://www.yenc.org/ydec.htm or
- Yenc32 from http://www.yenc32.com or
- UUD32 from http://www.execpc.com/~mspankus
By saving the raw file under a common extension like .yenc and associate it with the decoder, you can double click on it and it'll decode automatically. You can also drag and drop the raw file on the decoder icon.
Beware that the command line decoder yDec.exe doesn't like spaces in its path.
Put it in "c:\temp\" rather than in "c:\my temporary files\".

Outlook: Use yProxy or Fidolook.
Manual method: "To use yEnc with OE just combine and decode, save as an .eml file to the folder you have the decoder in. Go to explorer, navigate to the decoder folder then drag the .eml file to the yenc decoder and drop - result: decoded files."
[tip from Seawolf]

Netscape: The latest Netscape/Mozilla/Thunderbird have (limited) yEnc support.
Upgrade, or use yProxy above.
Manual method: make sure you save it under an extension that Netscape recognizes as binary (you can add/modify those in Preferences.) Or use a program on the saved file that strips the CR/LFs that Netscape added when saving (nocrlf, for example). Then drop onto yDec.exe.

Other Windows programs:
DecodeShell, decode email attachments: http://www.funduc.com/otsoft.htm - free
yEnc PHP Class: http://www.wonko.com/yenc/
DBX Plugin for Windows Commander: http://labs99.msk.ru/dbx
EncoderWizard, ActiveX control: http://www.seekfordsolutions.com/Products/EncoderWizard - evaluation copy

Diiva for OSX: http://www.diiva.com
Halime, free OSX newsreader. Discontinued but with source code: http://halime.imdat.de
Hogwasher (OSX): http://www.asar.com
MT-NewsWatcher (OSX): http://www.smfr.org/mtnw/downloading.html
Newsflash, free newsreader for OSX: http://sourceforge.net/projects/newsflash
NewsHunter (OSX): http://www.eridanus.com/
NewsHunter Classic (OS 9): http://www.eridanus.com/
PictureSnooper2K, for System 8.5 or later: http://www.qsyssoft.com/PictureSnooper/psframe.html
PixNewsLite X (OSX), for pictures: http://www.macupdate.com/info.php/id/7596
PixNewsLite, for pictures: http://www.macupdate.com/info.php/id/7595
PixNewsPro early beta: http://www.techsono.com/pixnewspromac
Picture Patrol Officer X/9: http://www.brainchild.nl
Thoth, Rosetta: discontinued. The old url is http://www.thothsw.com
Unison, downloading tool: http://www.panic.com/unison
yEnc TZ - freeware decoder: http://www.turbozen.com/mac/yenc

MacOSX: see also Unix below.
BNR2 for Linux: http://www.co.jyu.fi/~ap/bnr.html
Bnews for Linux: http://users.pandora.be/stef
Diablo, newsfeeding/newsreading server software for FreeBSD/Linux/Solaris/etc.: http://www.openusenet.org/diablo
Getbinnews, for i386/Linux,OpenBSD,FreeBSD: http://www.getbinnews.com
KNode for KDE: http://knode.sourceforge.net
Pan for Gnome: http://pan.rebelbase.com
Pimppa, binary tool: http://pimppa.sourceforge.net
UBH - Usenet Binary Harvester: http://ubh.sourceforge.net
yDec, decoder for Linux: http://sourceforge.net/projects/yenc
yencode, encoder and decoder: http://www.yencode.org

C code for Unix: ydec_unix.zip. Compile and run.
Improved C code: ydec_unix_stdin.zip. Compile and run.
Compiled Linux binary and source code: http://yenc.datastacks.com/~mouse/yEnc/downlaod.html

Unix users can also use WINE and Windows software.
Various O/S:
MacOSX, OS Independent, POSIX: yydecode at http://sourceforge.net/projects/yydecode
POSIX: Brag at http://sourceforge.net/projects/brag

yD - yEnc decoder ftp://ftp.sunet.se/pub/OS2/hobbes/os2/util/archiver/yd01.zip
UUDeview ftp://ftp.sunet.se/pub/OS2/hobbes/os2/util/archiver/uudeview-0.5.17-os2.zip
yEnc decoder ftp://ftp.sunet.se/pub/OS2/hobbes/os2/apps/internet/news/util/ydec-os2.zip

Japanese XacRett: multi decoder http://hp.vector.co.jp/authors/VA023546/soft/xac4ce.html (jp) http://hp.vector.co.jp/authors/VA017441/lib/xacrett.en.html (en)

NewsCoaster, open source newsreader: http://newscoaster.tripod.com

NiceStep, set of Java Beans: http://nicestep.sourceforge.net

WebTV (now MSN TV):
Use a web-based newsserver that supports yEnc in the meantime, until WebTV upgrades their software.
Note: WebTV hardware cannot store binaries. [http://webtv.net/what_faq.aspx#15]

Manual decoding has been reported workable:
"The AOL newsreader views the yEnc files as text. So set the groups that you want to read from to download to a folder for storing those text files. Then simply run yDec or yenc32 on it and it will decode all the files in one go." [tip taken from Giovanni]
Using another newsreader:
I have read that no third-party newsreaders are accepted by the AOL newsserver, and that because it uses a non-standard NNTP protocol even yProxy won't work; therefore if you want to use another newsreader, consider one of the free public news servers or one low cost newsfeed service. Or a web-based newsserver that supports yEnc.

Q and A

Q. What are .ntx extensions?
A. A ntx is created by yenc32 (www.yenc32.com), usually for tests only.
If you see a ntx on usenet it means the poster converted his binary to ntx with yenc32 and then uploaded that ntx, probably using the default UUencode. Posting in UUencode a ntx file defeats the purpose of yEnc and is useless in terms of bandwidth savings. If one wants to post in yEnc, one uses an yEnc-enabled posting program.
As for decoding the ntx file you downloaded, drop it onto yenc32 or another manual yEnc decoder.

Q. Xnews says I downloaded the binary but the file is not saved?
A. Xnews L5 ignores binary posts done in yEnc v1.3.
Solution: upgrade your Xnews L5 to version 5.04.24 or above: http://xnews.newsguy.com

Q. What is the best client software?
A. I have yet to find the perfect newsreader. All the ones I tried had various pluses and minuses. You could opt to use two clients, for example one for reading text and replying and another for binary downloading.

Q. Since a few days I cannot download yEnc posts anymore.
A. Some versions of ZoneAlarm v5 corrupt yEnc posts. Use another version or another firewall. Or turn off mail filtering.

How about a posting program?
o PowerPost-A&A is at http://powerpost.cjb.net and is the most up-to-date version of PowerPost. Can limit the bandwidth, can use multiple servers. Can do PAR2 as well.
o Here is good old YencPost2002v102.zip for Windows (500k.) Can switch yEnc/UUencode. Auto-adds "yenc" in the header and quotes around the filename.

o Posting notes:
Beware to not set the number of lines too high as yEnc has a longer line length, about the double of UUencode.
It has been suggested to stay in the 3000-4000 range or lower (or 350-400k per segment.)
Make sure that the last name in the subject is the filename ($F) otherwise some newsreaders like Agent, Gravity, NewsRover, NewsWatcher, Pan etc. won't be able to auto-combine the multiparts.
o Do not use "Power-post 2000 Build 25b yEnc" from the CosmicWolf.com site, it's broken.
It generates a wrong CRC for each single file so yEnc decoders will stumble on those despite the file may be okay.
Tip for Agent users:
Open AGENT.INI in the Agent folder, look for the line RequireFilenameWithTag=1 under [Attachment],
change it to RequireFilenameWithTag=0. Now Agent will auto-combine those tricky headers. On occasion it will wrongly combine headers that shouldn't be joined, though.

Osiris, for use with Thoth (OSX): http://beam.to/woodenbrain
Linux, Windows:
ypost, command line program for posting: http://sourceforge.net/projects/ypost
yencee, command line program for posting: http://sourceforge.net/projects/yencee

Alternative/older methods

o QP-Lite: integrated in Binary Boy Pro only. http://www.yenc.org/download/yEnc-History(English).htm
o BN encoding: has BPST in the encoded headers. Is being phased out in favor of yEnc. http://b-news.sourceforge.net

Last update: Jul 2005, added MyNews