'Forbidden Access' error and 'tag in POST' error while publishing / editing article in Joomla

Forbidden Access error, and 'tag in POST' error? while posting in http://www.doh.gov.ph/bihc_doh

This has not occurred before: frontend editing saves are rejected with a message 'Forbidden Access (flooding)' - or 'Forbidden Access (tag in POST)'. This is with Joomla 1.0.12 and 1.0.13 versions.

This is either (a) a Joomla built-in security block being triggered, or (b) more likely a server setting perhaps. I'm seeing it especially on Apache 1.1.3x / Unix servers.

If you Save and edit with a few words of plain text, it seems to be OK; but a fair-sized page with plenty of mixed content gets blocked - probably because of the number of HTTP requests at one time?

Of course, it means that frontend editing is impossible, which makes any kind of community use out of the question. Thought this was a joomla issue or server setting, but obviously an extension issue.

Solution:

Turn off security features of SH404SEF, that is of course assuming you have had the extension installed (being the issue here) :D