On 3-14 or 3-15 I started a thread concerning a new url for my web page at
. After the original post I added two more. Then a few days ago I
started to add another post, but the thread had disappeared.

Can anyone tell me how a thread disappears? Can it be deleted? By just anyone?

There's no universal mechanism for a "thread". It depends on your
news server and your newsreader.

Threads are often based on headers placed in the newsgroup articles...
when one posts a followup, the newsreader usually adds a "references:"
header which gives the article-ID of whatever message you're posting a
followup to. Newsreader programs, or Web-based newsreading services
can use these "references:" headers to deduce the linear or tree
structure of a thread of articles.

Some newsreaders don't use this information, and try to deduce the
thread structure by looking at the 'Subject' headers.

In either case, there's no standard for how a system maintains a 'list
of active threads', and there is no centralized registry. Each system
which stores and processes USENET news (Giganews, Supernews, Google,
and numerous smaller servers) has the ability to maintain its own
thread database, makes its own decisions about how such databases are
constructed, and makes its own decision about how long to store the
thread information and the underlying articles themselves.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
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