Reconciling Accounts

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Hello,

The company that I just started working for, switch from using MAS 90 to Sage 50. I had to input all the information from the beginning of January 2014 until now. I am trying to reconcile my general account. However in the statement that was sent to us for the month of January, it is showing transactions that happen before January. The un-reconciled difference is the amount of transactions that happen before January. 

I hope that makes sense. My question is how can I reconciled the account with double posting transactions? 

Thanks in advance.

Liz P.