If the grant was posted in a prior year, and you just changed the fund class code for only the current year, the GL account numbers will not be available when you try to change journal history (see. How do you change the cash account on a posted voucher? )

We recommend that, when changing fund class codes, you change them back to the beginning of the fund (see How do I change fund codes?).

To correct this situation-preferred method:
  1. Change the fund class back to the original for the current year
  2. Change again to the new correct code using the oldest fiscal year through the most recent. 
  3. You should now be able to change the cash account number in AP history.

In more recent versions of FIMS, validation of the GL accounts on the voucher should occur against the current fund code structure and this process will not be required.