Originally, the Usenet was invented for discussions, i.e., exchange by textual messages. So, Usenet software and protocols were developed with this limitation in mind: all messages are textual.

When it was realised that it would be good to be able to post binary files as well, it presented a problem. Binary files, e.g. pictures, contain all sorts of byte codes, not only textual. Posting them meant violating the "text-only" limitation that had been built into Usenet software and protocols. So, the software would not accept binary files or would not work properly with them.

This problem found a simple solution: let's encode binary files in such a way that they contain only acceptable byte codes, and then we can post them. This is what encoding is for. Normally, encoding and decoding is performed transparently by your mail and news software and you don't have to know anything about it.

All encoding methods (uuencode, xxencode, base64 and binhex), except yEnc, use the same basic principle: they replace every 3 bytes of the original binary file with 4 bytes from an encoding table that contains only textual codes. It is a bit more complex than that, but this is the idea.

When you download an encoded file from the Usenet, your decoder performs the reverse transformation and you end up with the original binary file.

Please note that the size of the encoded file is at least 33% larger than the size of the original binary file.

yEnc is based on the recognition that not all "non-textual" byte codes are "bad" for the Usenet, but only a few of them. The rest can be posted and processed by Usenet software without any problems.

yEnc encodes binary files in two steps: first, it changes each byte by a constant in order to minimise the amount of "bad" bytes in the file. Second, it replaces each "bad" byte with a unique sequence of two bytes. Again, it is a little bit more complex than that, but not much.

As far as we know, this process increases the size of the encoded file only by 2-3% on average.

We don't see why yEnc is less safe than any other encoding method.

Generally, the Usenet is not very safe at all. Anyone can post infected software or just a bomb that will wipe out your hard drive. There are claims that playing music and videos downloaded from the Internet can infect your computer.

If you are concerned with your privacy and security of your computer (most people are), there are a few things that you should do:

• Do use an anti-virus. There are plenty available.
  
  
• Do use a firewall. Firewalls protect you from hackers attacks. Norton Personal Firewall is a good choice. We tried two other quite popular firewalls, but they were causing problems.
  

• Do check your computer for spyware regularly and remove it. A good free tool is Ad-Aware (recommended).
  
  
• Do not start executables and .bat files downloaded from the Usenet unless you are absolutely sure that it is safe.
  

There are a few options that you have:

• Ask your newsreader developers whether they are going to implement yEnc decoding. Chances are, they are going, but you would have to wait.
  
  
• You can try to download messages containing yEnc encoded attachments and save them as files on disk, then run a yEnc decoder on them, available from here. You may succeed, but it is not guaranteed, because in the process of working with a yEnc encoded message your newsreader may correct "inappropriate" bytes and thus, corrupt the encoded file.
  
  
• Find another newsreader that does support yEnc. There are plenty by now. Most people reading this are Outlook users. Outlook is a very good tool, but not a binary newsreader. If you are interested in yEnc, you must be working with binaries. Get a newsreader designed for that. As someone wrote in their post, "get a real thing and you will never look back." See what Ozum can do for you. It is especially good for images. Download and try it for free, feel the difference. What do you have to loose? You will get more than just yEnc support.
  
  
• There are a couple of applications that you can use as yEnc proxies. A yEnc proxy is a program that sits between a news server and users newsreaders and replaces yEnc encoded attachments with the same attachments encoded using some other method. Thus, newsreaders that do not support yEnc, can decode attachments that were originally encoded using yEnc if they receive them via an yEnc proxy. You can run such a program on your own computer. First one of these applications is Ozway. The other one is yProxy. They are both free, but slightly different.

  Ozway was designed and built to work efficiently primarily in multiuser mode. It is used by ISPs and commercial news providers. Ozway is multiplatform (Windows, FreeBSD and Linux), fast and does not have a practical limit of number of simultaneous connections. However, it is also very small (smaller than yProxy) and can be used by individuals.

  yProxy, though can be shared, is an individual application. It has a limit of 10 simultaneous connections.

  Both Ozway and yProxy are limited to be used with one news server, but you can install and run several copies, to access multiple news servers simultaneously. yProxy has a GUI interface, Ozway relies on text configuration files. yProxy is simpler, but Ozway seems to be more reliable.

Given that you can use a yEnc newsreader for free for a month, we strongly recommend to try it before you start messing with yEnc proxies. What do you have to loose? You don't have to buy it after the trial period is up. The feedback from people who tried the "proxy way" is mixed.

Some posters do very irrational (to put it politely) thing: they first encode files manually with yEnc encoder, than post these files. In the process of posting, their posting software encodes these files again using some other method, for example, uuencode.

Then, when you download such files, your newsreader recognises that they are uuencoded and decodes them. But, it is not aware that that was only the second level of encoding. So, what you have now are yEnc encoded files. To get the original files, run yEnc decoder on them. You can download it from here.

Upgrades are free within a major version. E.g. if you have version 5.00, you can use any 5.xx version. Upgrading from version 4 to version 5:

If you registered version 4 in the interval between the 7th of September 2008 and 7th of November 2008 - the upgrade is free of charge. Send us your ref number or full postal address and we will send you a license.

If you registered version 4 in the interval between the 7th of May 2008 and 6th of September 2008 - you can upgrade if you pay $10 as license processing fee. Send this payment to payment@ozinsight.com via Paypal. Include your ref. number and/or name & full postal address.

This offer is open till February, 10 2009.

It is an image index, but a bit better than just that. Indexes are there to save time and money. Double click indexes save more time and more money. When you use a "normal" index to select and download images, you have to memorize file names and then search article headers to find and download articles that carry these files. This takes about 5 seconds (at best) per selected article, if the collection is small (within a hundred of articles) or 10 seconds and more if the colection is large (several hundred or thousands of articles).

When you use a double click index, selecting and finding of an article takes as long as it takes you to point to a thumbnail that you like and click on it. This is about 1 second, and this time does not depend on the size of the collection. Ozum finds the article automatically for you. The process is very easy and effortless. Relax and enjoy. Just double click on what you want and get it.

No. This is a common misconception. People think that double click indexes are about downloading images from some affiliated Web site. This is not true. The truth is, the images are downloaded from your newsserver and your current newsgroup. The difference is only in finding them. If you use a "normal" index, you have to find the articles yourself. If you use a double click index, your newsreader (Ozum) finds them automatically, using the information that links the thumbnails in the index to the articles subjects, posters and message-IDs.

If the image, corresponding to the thumbnail you are pointing to, can not be found in the group, Ozum displays "not available" on the bar below the index image. This means that this article is not found in the list of articles. Possibly, it has expired, has not made it to your server, or you have deleted it from your list of articles.

There are 2 ways:

a) If posting a collection of images using Ozum, just tick a checkbox, and Ozum will create and post indexes automatically with your collection.

b) Using Ozum, you can post indexes for a collection that has been posted already by you or someone else. Select collection articles, right-click on it and select "Create Index" in the context menu. Fill in index parameters and click on "Start Now" when finished. Ozum will download the articles (if not downloaded yet), create indexes and post them.

It looks like you did not save the textual part of the index after downloading it. When you download an article by double clicking on it, Ozum automatically saves the text part and the binary attachment(s). When you download a set of articles in a batch (downloading job), Ozum gives you an option to choose whether you want to save textual parts of articles, or attachments, or both. Make sure you save both. Both parts are important for indexes. The text part maps thumbnails to the articles that carry the images.

RAR (.rar) files are created by WinRAR archiver. This format makes it easy to create multipart volumes and therefore it is easy to split large files into parts using WinRAR. This is the preferred format for posting of compressed files on the Usenet. Posting in other formats, such as zip and ice does happen, but is strongly discouraged.

Generally, posting compressed files in the News does not seem to be a very good idea, especially posting images. If they are posted in an archive, you have to download the entire archive even if you want to have only a few of them.

Size reduction benefits achieved by compressing images, movies and mp3 sound files are very insignificant because contents of these files are already compressed using medium-specific compression techniques, and it is hard to compress them more without loss of quality.

It seems that the only thing that justifies using rar format for posting, is the ability to create multipart volumes and error recovery files.

Error recovery files (parity sets, par) are redandant additions that often are posted with multipart files, such as rar archives or files created by MasterSplitter. When available, parity sets can be used to recover any missing part of the file. As many parts can be recovered as there are parity sets available. Parity sets are good for error recovery and nothing else. You don't need to download parity sets or even think about them if you have all parts of the multipart file available.

There are two forms of file names generated by WinRAR. The first one is <name>.part##.rar, where '##' is part number, starting with 01. Example 1:

Moody Blues Days of the Future Passed MFSL.part01.rar
Moody Blues Days of the Future Passed MFSL.part02.rar
Moody Blues Days of the Future Passed MFSL.part03.rar
Moody Blues Days of the Future Passed MFSL.part04.rar
...

The second form is <name>.r##, where '##' is either 'ar' or part number, starting with 00. Example 2:

Beatles - Rubber Soul.rar
Beatles - Rubber Soul.r00
Beatles - Rubber Soul.r01
Beatles - Rubber Soul.r02
Beatles - Rubber Soul.r03
...

Parity sets, or error recovery files, can be posted with RAR files named in any of these two ways. Parity sets are normally named <name>.P## where '##' is set number, starting with 01. A file with name <name>.par is normally included in the post and contains information used for parts checking and recovery. It is sort of a header/summary/info file.

Example 1 plus parity sets:

Moody Blues Days of the Future Passed MFSL.part01.rar
Moody Blues Days of the Future Passed MFSL.part02.rar
Moody Blues Days of the Future Passed MFSL.part03.rar
Moody Blues Days of the Future Passed MFSL.part04.rar
...
Moody Blues Days of the Future Passed MFSL.par
Moody Blues Days of the Future Passed MFSL.P01
Moody Blues Days of the Future Passed MFSL.P02
Moody Blues Days of the Future Passed MFSL.P03
...

Example 2 plus parity sets:

Beatles - Rubber Soul.rar
Beatles - Rubber Soul.r00
Beatles - Rubber Soul.r01
Beatles - Rubber Soul.r02
Beatles - Rubber Soul.r03
...
Beatles - Rubber Soul.par
Beatles - Rubber Soul.P01
Beatles - Rubber Soul.P02
Beatles - Rubber Soul.P03
Beatles - Rubber Soul.P04
...

Please note that parity sets can be created for any multipart set, not necesseraly a rar file. For example, they can be created for and posted with files split by MasterSplitter:

my_loved_kittens.mpeg.001
my_loved_kittens.mpeg.002
my_loved_kittens.mpeg.003
my_loved_kittens.mpeg.004
my_loved_kittens.mpeg.005
...
my_loved_kittens.mpeg.par
my_loved_kittens.mpeg.P01
my_loved_kittens.mpeg.P02
my_loved_kittens.mpeg.P03
...

If using Ozum 3.0 or later, double click on any article carrying any part of a multipart file. Ozum will recognize the name format automatically, will search the list of articles for the .par (info) file and other parts, check if they are complete, check if parity sets are available present this information to you and then download, recover (if needed) assemble and unpack the file automatically.

Read further only if using other newsreaders, such as Outlook Express etc.

You will need some extra software. You can download WinRAR (shareware) from this site:

http://www.rarlab.com/download.htm

You may need SmartPar to recover missing file parts using parity sets SmartPar is free. You can download SmartPar and a lot of other par related tools from this site:

http://parchive.sourceforge.net/

Associate .par extensions with SmartPar and .rar extensions with WinRAR.

1. Download all parts to a single directory. By "parts", we mean whole files with names as described in 3.2 above. Such files usially are split again when posted. The way to get them together, depends on your newsreader.
2. If some parts are missing, download and save to the same directory as many parity set files as there are parts missing. You can use any parity set file to replace any part.
3. Download and save to the same directory .par file included in the post.
4. Open the directory in Windows Explorer..
5. Double click on the .par file. SmartPar should start and check the file(s) and recover missing part(s) if any.
6. Open .rar file in WinRAR. You can unpack it now.

You can gather your files from multiple servers using Ozum. To get a file together, do this:

1. Download all parts to a single directory. By "parts", we mean whole files with names as described in 3.14.2 above. Such files usially are split again when posted. Ozum will combine them automatically for you
2. If some parts are missing, download and save to the same directory as many parity set files as there are parts missing. You can use any parity set file to replace any part.
3. Download and save to the same directory .par file included in the post.
4. Open the directory in the directory tree on the left. You will see a list of files in the directory.
5. Double click on the .par file. If all the necessary files are there, Ozum will automatically recover missing parts using parity sets, if needed, then assemble the original file and unpack it to the current directory.

If you are using other newsreaders, do steps 1-3. To do steps 4 and 5, you need extra software. See 3.3.

Use WinRAR to create multipart archives. WinRAR is shareware. To the best of our knowledge, there are no other tools to create archives in rar format because it is patented. You can download WinRAR from this site:

http://www.rarlab.com/download.htm

Use SmartPar to create parity sets (error recovery files) for your multipart archive. SmartPar is free. You can download SmartPar and a lot of other par related tools from this site:

http://parchive.sourceforge.net/

When done, post the resulting files, including the created .par file.

This is also a parity sets format. Unfortunately, it does not define any rules for naming parity sets. So, there is no way for newsreader software to establish association between the files and their parity sets. This is why Ozum does not process PAR2 files automatically. You can recognise files in this format by .par2 extensions and '+' in extensions of some filenames. If you come accross this format, download the files and parity sets (if needed), and use free QuickPar utility to process them. You can find QuickPar here:

http://parchive.sourceforge.net/

NZB files are files in XML format containing information helping to assemble multipart posts. Some newsreaders use them for this. If you use Ozum, you don't need NZB files because Ozum assembles multipart posts automatically.

Just double click on any part of a multipart post and Ozum will find all the parts and ask you whether you want to download whole file or only a part of it.