Message: Exchange rate must be greater than: 0
To process invoices with foreign currency in Zenvoices, the currency must be created in Exact Online.
In Exact Online go to Financial / Analysis and results / Currency / Exchange rates and click 'New' to create a new currency. If the currency already exists, check the start date. The start date must be earlier than or equal to the invoice date. If required, you can add the currency from another date via Add.
Message: Not allowed: Currency
In Exact Online go to Financial / Analysis and results / Currency / Exchange rates and check whether Use the exchange rates of the current administration is enabled.
Also check whether foreign currencies are allowed for the journal you are using. In Exact Online go to Master data / Financial / Journals / Purchase journal or sales journal and check whether Variable: Currency is enabled.