PK field, indexed-no duplicates shows twice in query

[jhollingsh615]

AC 2007 split BE/FE, running on Windows 7.
The core table is basically a list of office contacts, with an autonumber field as the PK, indexed with No Duplicates. But, from time to time, a query based on this table and several others, will return the same PK field multiple times.



I suspect it is something basic that I've totally screwed up and/or neglected. But, I'm at a loss.

[RuralGuy]

This can happen in a query if you have a problem with the Join.

[orange]

Further to Allan's response, can you show us a query where the problem occurs.