Gyration Ultra mouse and keyboard not working.

I've got a conference room computer that has the Gyration Ultra mouse
and keyboard, but I can't seem to get them to work. The user states
that they used to work fine. The batteries are new. I checked the
channels and set them to the same channel (they're supposed to be on
the same channel, right?). I redid the Learn/Teach. But still nothing.
They clearly have power. My understanding is that these use the default
Windows drivers. I've been to Gyration's website, and there was
absolutely no help there. I even emailed their tech supprt, but they
just won't aget backc to me. Any ideas?

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