I've been through every post I can find, all over the web, and have been unable to locate a solution. I have the dreaded "undefined function error" in a query (Access 2000 on an XP machine). I've experienced this with several functions and I'm getting tired of writing the functions myself. I've checked all the references, none are missing. I've unchecked and rechecked references, compiled ad nauseum. I've replaced references, I've repaired and compacted, I've created new databases and imported objects. Does anyone have any other solution? Thanks for your help!