PlanMaker ISERROR: Detect errors without concealing their cause

The PlanMaker 2026 reference, 2024 reference and 2021 reference were retrieved and compared on October 15, 2026. They document this function’s core operation. Documented by 2021 is not an original introduction date; the first introduction and any last-working-version endpoint remain unverified. The 2026/NX manual family does not establish per-build availability in FreeOffice, mobile clients or every operating system.

The examples below are vendor-supported controls and independently modeled expectations. No native PlanMaker execution, screenshot capture or workbook interchange test was performed. Keep the distinction between documentation support and observed application behavior when applying the guide to an installed version.

=ISERROR(Cell)

There is one required argument and no documented optional default. Use a single-cell reference such as A2 for the worked tests. The examples deliberately keep the inspected value in a visible source cell. The formulas use English function names. The one-argument call needs no list separator; nested helper formulas below use commas, which may need adjustment for the installed locale.

Create ErrorAudit with Entry, Error_flag, Other_error and Missing_flag in A1:D1. Enter the following A values exactly. An entry beginning with = is a formula. Fill B2 =ISERROR(A2), C2 =ISERR(A2) and D2 =ISNA(A2) through row 8.

The text in row 5 merely spells an error label. Row 4 contains the actual error supplied by NA. The empty string in row 7 is also a formula result, yet it is not an error. SoftMaker’s error-value reference describes error categories; the three predicates select different subsets rather than performing three different repairs.

In a copy, replace A3 with =1/2. A3 becomes 0.5, and B3/C3 become FALSE; D3 remains FALSE. The original A8 error is still present. This one-cell repair is a better audit control than overwriting every error with zero.

Create CartonRatios. Enter Items in A1, Items_per_carton in B1, Ratio in C1 and Review in D1. Enter numeric pairs (24,6), (10,0), (0,4), (15,5) in A2:B5. Fill C2 =A2/B2 and D2 =IF(ISERROR(C2),"Check calculation","Calculated") through row 5.

Expected C is 4, an error, 0, 3. D is Calculated, Check calculation, Calculated, Calculated. Zero in the third row is a valid ratio for zero items; it must remain distinguishable from the undefined second-row division. Change only B3 from 0 to 5 in a copy: C3 becomes 2 and D3 becomes Calculated. Nothing in this test establishes whether the result is an integer number of full cartons; that is a separate business rule.

For a simple count, place E2 =IF(ISERROR(C2),1,0) and fill through E5. =SUM(E2:E5) is expected to be 1 before the repair and 0 afterward. A status column preserves the original error for investigation while providing a numeric review count.

A FALSE result means only that the inspected value is not an error. A wrong price, stale date or text value can still pass. Check the source formula and its dependencies, rather than treating this as a correctness certificate.

Use a real cell reference without quotation marks. ISERROR("A2") would supply text, not ask about A2; the published signature is cell-oriented. Multi-cell array evaluation, text coercion, direct expressions, localized error displays and exact behavior in older installations are outside this worksheet specification. A malformed outer formula is not repaired by putting ISERROR inside it.

ISERR excludes #N/A, while ISNA identifies only #N/A. IFERROR is a replacement operation. Choose between a visible audit flag and a fallback according to whether the original failure must remain visible.

Record the PlanMaker version/build, edition, platform, language and workbook format. Recreate the original dataset, inspect the actual formulas and then apply the specified one-cell changes on a copy. Compare the original and changed outputs, not only a screenshot of the final values. Save/reopen and cross-product import results remain separate tests; neither was performed for this guide.