The error message comes from the Exact Online accounting package.
Please control the following settings in Exact Online:
Financial => Analysis & Results => Currency => Exchange rates
- Select the option for: Use the exchange rates from the current company
- Do not use the option: Use the exchange rates from the company
Financial => Analysis & Results => Currency => Exchange rates
- Click on the currency code
- Can you see the invoice date under the section Exchange rates?
- If the invoice date is not listed here, can you Add the new exchange rate?
Settings => Financial => Journals => Purchase
- Is there a check-mark next to "Variable: currency?
- If no, select this field by putting a check-mark
- Is there also a check-mark for "Variable: Exchange rate?
- If yes, de-select this field so that it is not selected
