Access Query ??

I'm trying to build an append query in Access 2002. If I Select Query the main table and put criteria on it (yes/no field = yes), it will select the proper records, no problem. However, when I simply add the table I'm going to append to into the query, the Select Query magically doesn't work anymore. I remove the appending table, and *poof!* it works again. Any thoughts?

(edit) Note: The selection still will not work even if I remove the criteria, so long as I have more than one table linked. I'm basically trying to pull the entire table (PMWOLIST), but if I have the appending table (PMWO) in the query table list, the query doesn't work.