I just discovered something odd which may be be related to this
problem.

The PHP book I am reading says that MySQL recommends downloading and
installing the latest PHP connectors, mysql.dll and mysqli.dll, and it
gives instructions for doing so. The reason it gives is that the
MySQL site's connectors will always be current, while those downloaded
with a PHP distribution may be a few weeks old.

I thought I'd do this to eliminate old connectors as a possible cause
of the phpMyAdmin problem, but I found that:

1. Only the mysql connector was installed with PHP -- mysqli was not.

2. The mysql connector was version 5.0.45, and my MySQL (the latest
stable version, as of a few weeks ago) is 5.0.51a.

3. The latest mysql and mysqli connectors on the MySQL web site are
even older than the mysql connector from the PHP distribution --
5.0.27. This conflicts with what the book advised me, and is rather
surprising!

I'd like to ask for advice before I start trying various combinations
of connectors more or less at random. Is this situation likely to be
related to my phpMyAdmin problem? If so, what is a good strategy for
cleaning it up?