While reviewing JC-M to confirm that closed WO's are not in WIP (an earlier ongoing problem),  we have recently discovered 12 closed WO's from 2001-02 ???  with large amounts remaining in WIP. The total Cost is more than $8000!
 
The WO's are for the same parent part.  It appears that a "make from"  part listed on the BOM did not get captured in the WO receipt to finished goods though it was issued along with the other BOM parts.
 
The strange part is these WO's had cleared WIP (based on earlier reviews/reports) but somehow have now shown up!!  
 
The only thing I can think of that may have triggered this is -Within the last 3 months or so, we made changes to the BOM list to set up the outside processing of material that then goes into the finished part.  We created the "make from " part and added it to the BOM.  I'ts very possible we have the set-up wrong but...
 
Nevertheless, recent changes to a BOM shouldn't effect old closed WO's  - right?   I am perplexed.  
 
Any thoughts on what to do??
 
 

Changes to BOM or routings have never affected my closed work orders.  
 
I had problems with this a long time ago and discovered the close date was 00/00/00 causing a problem when I ran reports.  
 
Also, we consistently had amounts "hanging" in WIP in closed work orders back in the 2003 time area.  The problem has cleared since then.