I found another solution for this error. Instead of setting up a dummy exchange rate, if you remove triangulation, then this will also fix the error:
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General Ledger > Setup > Currency > Currencies and locate the EUR currency. You should see that the Reference currency for triangulation box is checked.
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to remove the checkmark from the Reference currency for triangulation box go to General Ledger > Setup > Currency > Denomination Currencies and remove the denominational currencies listed there. Once complete remove the check box from the Reference currency for triangulation check box.