About Manually Prorated Amounts
You can post a receipt only when the you have completely allocated any additional costs you selected for manual proration, plus their associated tax amounts.
Tip: Check the Totals tab to see whether you entered all manual proration amounts.
You can manually prorate additional costs only to item details, including non-stock items, that have valid inventory item numbers. You cannot manually prorate costs to non-inventory items.
In multicurrency ledgers, you can manually prorate additional costs only for vendors who use the functional currency.
Note: For a job-related receipt, you can prorate additional costs to different contracts, projects, and categories. However, if you want to allocate an additional cost to several jobs, you need to add a receipt detail line for each job.