Business Central checks the sign of Amount against the Document Type on the line before it posts. A vendor payment and a customer refund have to be positive, while a customer payment and a vendor refund have to be negative, and the journal stops as soon as one line contradicts that. Correct either the sign of the amount or the document type on the line named in the message, here line 10000 of batch DEFAULT in template GENERAL.
Why Business Central checks the sign
Document Type is not a label, it is what tells the ledger in which direction money moves and which open entries the line may be applied to. A payment to a vendor reduces a payable, so on a vendor line the amount is entered positive and the balancing bank account takes the other side. A receipt from a customer reduces a receivable, so on a customer line the amount is negative. Refunds are the mirror of each of those. The posting check refuses any line where the two disagree, and the same check produces the twin message must be negative when the sign is wrong the other way round.
- The document type was left as Payment on a line that is really a refund, or the other way round, after a line was copied or a batch was reused.
- The figure was typed in the wrong column: entering it as a credit amount makes Amount negative, entering it as a debit amount makes it positive.
- The account and the balancing account were swapped, so the vendor or customer sits on the balancing side and the sign of the whole line is inverted.
How to correct the journal line
- Open the journal named in the message: search for General Journals (Alt+Q), then select the template GENERAL and the batch DEFAULT.
- Find line 10000 and read three fields together: Document Type, Account Type with Account No., and Amount.
- Apply the rule for that line: a vendor payment and a customer refund are positive, a customer payment and a vendor refund are negative. Change the sign if the document type is right, or change the document type if the amount is right.
- If you work with separate debit and credit amount columns rather than Amount, move the figure to the other column instead of typing a minus sign.
- Check Bal. Account No.: the vendor or customer belongs on the line itself and the bank or cash account on the balancing side, not the reverse.
- Use Apply Entries on the line to attach it to the invoice or credit memo it settles, which also confirms the direction the ledger expects, then post.
How to avoid it next time
Most sign errors come from typing lines by hand into a general journal. Letting Business Central build them removes the guesswork: the suggest vendor payments function in the payment journal fills document type, sign and applied entries in one run, and importing bank statements with automatic application does the same on the receipts side. When lines are entered manually, applying each one to its open entry before posting is the quickest check, because an application that refuses to attach usually means the direction is wrong.
Frequently asked questions
What does the twin message must be negative mean?
It is the same check seen from the other side. It appears when a customer payment or a vendor refund carries a positive amount, and you correct it the same way, by fixing either the sign or the document type.
Why does the message quote a template and a batch?
Because the check names the exact record it stopped on. Journal Template Name, Journal Batch Name and Line No. together identify one single line, which matters when several people work in different batches of the same template.
Related reading
- Payment Journal, The Business Central journal for paying vendors, with automatic payment suggestions, application to open invoices, and payment file export.
- Vendor Ledger Entry, The detailed transaction log in BC recording every financial event related to a vendor, invoices, payments, and credit memos.
- Customer Ledger Entry, The transaction record in Business Central tracking every posted invoice, payment, and credit memo for a customer, where open entries show what is still owed.
- How to Pay Vendors with the Payment Journal in Business Central
- How to Import a Bank Statement in Business Central
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