We are planning a software upgrade on February 23, 2016 to the news server software that manages messages and headers. This upgrade enables our news servers to display the full depth of headers going back 7+ years to match our message retention.
As you may know or have experienced, some very active newsgroups do not display headers as far back as we have messages. (We could only display a finite number of message headers due to the variable field size in our message database.) Going forward, we can now display headers as far back as we have messages.
The upgrade will cause all the headers to be re-sequenced. Practically, what this means is that if you store headers locally on your PC, the headers retrieved up to now will no longer point to the expected message.
This should NOT affect the ability to use an NZB to retrieve messages.
If you store headers locally on your PC, you should purge them. In most Usenet client software, you can purge headers by unsubscribing from a newsgroup and then resubscribing.
If you do not store headers, no action is needed.
If you continue to use the old locally stored headers in your client after February 23rd, you will likely receive errors like “message not found” or “message out of server’s retention”.