The Opening Balance field is grayed out for new foreign customers and vendors because foreign opening balances involve exchange rates. Exchange rates can vary by transaction, so we recommend that you enter the individual transactions, with their respective exchange rates, that make up the customer or vendor opening balance.
Determine which transactions are currently open, as well as the exchange rates used, for the foreign customer or vendor you're adding.
Enter invoices and bills in QuickBooks to re-create those open transactions using the original exchange rates. Include the items you sold or purchased in the original transactions in the re-created transactions.
What to know about foreign customers and vendors
What to know about foreign transactions