Opening balance on reconcile window disagrees with account balance on any day

[Sidney Bludman]

Where does reconcile window get opening balance?  
How can I correct account balance so as to agree with reconcile window?

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Professor Sidney Bludman, Depto. Astronomia
Universidad de Chile, Casilla 36-D, Santiago,Cl
http://www.das.uchile.cl/~sbludman
(56-2)716-0204,   sbludman at yahoo.com