causes of "plugin entry point could not be found"

Hi,

I had a report from a user ofmy most popular plugin (i.e., mature and extremely well tested), that it failed to work for him on Photoshop CS3 Extended + Vista Business 32-bit.

The error message when he used the plugin was "Could not save as ... because the plugin entry point could not be found."

Is there anything new about CS3 Ext that might cause this? (The plugin is known to be compatible with Vista.)

I have not had other reports like this, so I am currently concluding it's an oddity of his installation.

--Toby