Find mistakes with Books Checkup

6 min · Beginner

Books Checkup looks through your books for the mistakes an accountant checks for at month-end: a bill typed in twice, a payment that never reached the bank, a transaction left uncategorized, an account nobody has reconciled, payroll tax past its due date. It runs on your computer, changes nothing, and tells you for each finding why it matters and what to do.

In this lesson you will

  • Run Books Checkup and read the summary
  • Open the transaction behind a finding and fix it
  • Ignore a finding that is correct, and bring it back later

Before you start

Books Checkup with a summary of findings and a bill that may be entered twice

Run the checkup

Run it once a month before you look at your reports, and always before you close the year or send your books to your accountant.

Step 1: Open Company → Books Checkup

The checkup runs as soon as the screen opens and takes a second or two. Check again runs it after you have fixed something. The most serious findings come first.

  1. The summary: how many items to fix soon, to review and to tidy up.
  2. Each finding says what it found, here a bill that may be entered twice.
  3. Go to opens the screen where you fix it.
Books Checkup screen with the summary bar, a duplicate-bill finding and its Go to Bills button marked

Step 2: What it checks

Bills, vendor payments and customer payments that look entered twice; invoice and check numbers used twice or missing; payments sitting in Undeposited Funds for more than 14 days; transactions in an Uncategorized account; downloaded bank lines not reviewed; bank and card accounts not reconciled for 45 days; reconciled transactions voided afterwards; overdue payroll tax deposits; a negative sales tax balance; dates that look mistyped; item receipts still waiting for a bill; unused customer and vendor credits; invoices more than 120 days overdue; negative stock; items priced below cost; and payments far larger than usual for that vendor.

Tip: Books Checkup finds bookkeeping mistakes in books that balance. Check Data (also on the Company menu) is the other check: it tests the file itself, such as entries whose debits and credits do not match.

Work through a finding

Step 3: Read why, then open the transaction

Every finding explains itself, and every line in it says exactly what was spotted. Open takes you to the transaction, where you can void a copy, fix a date or choose the right account. Then click Check again.

  1. Why it matters.
  2. What to do about it.
  3. What was found on this line, here the same vendor and bill number as an earlier bill.
  4. Open the transaction.
  5. Ignore hides this one line from later checkups.
A duplicate-bill finding with its explanation, what to do, the reason on the line, and the Open and Ignore buttons marked

Step 4: Ignore what is correct

Sometimes a finding is right: two equal bills really were two orders, or a payment really is post-dated. Click Ignore on that line and it stops appearing. The line under the summary counts what you have ignored, and show them again brings every ignored item back.

  1. The ignored count and show them again.
Books Checkup after ignoring an item, with the ignored count and the show them again link marked

Recap

  • You can run Books Checkup from the Company menu.
  • You can open the transaction behind each finding and fix it.
  • You can ignore a correct finding and bring ignored items back.
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Questions

Does Books Checkup change my books?

No. It only reads them. Every fix is something you do yourself, on the usual screen, so it is recorded like any other change.

Does it send my data anywhere?

No. It runs entirely on your computer, with no internet connection needed.

Who can run it?

Anyone who can enter transactions. Ignoring an item hides it for everyone using that company file.

Is a finding always a mistake?

Not always. Each one is something worth a look. If it is correct, choose Ignore.

Screenshots from AcboBooks 0.2.2 with the built-in sample company. Updated October 25, 2026. Your screens may differ slightly with another version or window size.

Get started

Learn it on your own books.

Everything in these lessons works in the free 15-day trial. Start with the sample company, then create yours.

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