ISERR in Collabora Office: Separate Calculation Failures from Unavailable Values

• Introduced: original Collabora release and launch date are not established by the sources reviewed.
• Availability: documented in Collabora Office 26.04 help, scoped to the desktop-help release.
• Platform scope: support in every online or mobile deployment is not inferred from desktop documentation.
• Checked: October 14, 2026. Direct function-specific documentation and independently derived examples; no native Collabora test was performed.

=ISERR(value)

value is a referenced value or an expression. Collabora’s direct reference explicitly contrasts division by zero with NA(), returning TRUE for the former and FALSE for the latter.

ISERROR includes #N/A; ISNA identifies that one unavailable-value class. Choose the test according to the workflow rather than treating their similar names as synonyms.

Examples use English function names and semicolon argument separators. The flags classify values; they do not repair the source calculation or supply a replacement.

Create this control in A2:A7:

In B2 enter =ISERR(A2) and fill down. Only the division-error row is expected to return TRUE. The actual #N/A error and the literal text #N/A both give FALSE here, but for different reasons: one is the excluded error type and the other is not an error at all.

Retain the source values when interpreting a FALSE. The function’s name should not be expanded into the claim “no errors exist” without accounting for its explicit exception.

For A4 containing =NA():

=ISERR(A4)
=ISERROR(A4)
=ISNA(A4)

Expected results: FALSE, TRUE and TRUE. For A5 containing =1/0, the same three tests are expected to return TRUE, TRUE and FALSE.

These two controls are enough to reveal a mistaken substitution between ISERR and ISERROR. Test both before deploying a workbook rule that treats unavailability differently from a calculation failure.

Using the mixed control column, enter in C2 and fill down:

=IF(ISNA(A2);"Unavailable";IF(ISERR(A2);"Calculation error";"No error detected"))

Expected labels are No error detected, No error detected, Unavailable, Calculation error, No error detected, No error detected.

The #N/A text in A6 is not an unavailable-value error, so it receives the ordinary no-error label. If a source system represents missing data using text codes, define an additional explicit text rule. Do not silently pretend every matching-looking string is already a spreadsheet error.

The labels describe only spreadsheet error categories. A Ready status or numeric amount can still be inappropriate for the intended column despite receiving No error detected.

In two unused helper columns, map the tests to numeric flags:

=IF(ISERR(A2);1;0)
=IF(ISNA(A2);1;0)

Fill both down through row 7. The expected first helper is 0, 0, 0, 1, 0, 0, summing to 1. The second is 0, 0, 1, 0, 0, 0, also summing to 1.

The combined error total is two, but the separate totals preserve a useful distinction. In this controlled dataset, one value is unavailable and one expression has a calculation failure. That difference would disappear if every problem were immediately converted to zero.

=ISERR(0/5) is expected to return FALSE, while =ISERR(8/0) is expected to return TRUE. The first expression has a valid numeric result of zero. The second has no valid division result.

If a report needs a fallback, use a clearly defined handling rule and preserve the raw diagnostic columns. IFNA can target the excluded #N/A class; IFERROR has broader scope. The predicate ISERR itself only returns a flag.

A FALSE result may be a normal value, text, or the specifically excluded #N/A error. Add an ISNA column before deciding that every FALSE record is ready for downstream arithmetic.

Inspect the original formula and input types rather than replacing every flagged value with a convenient constant. The direct reference supports the two error controls used here; native execution, exact displayed division-error labels and exhaustive imported-type behavior remain unverified.

• Collabora Office 26.04: ISERR.
• Editorial testing standards.

Product-specific error classification comes from the direct Collabora help. Worked tables and helper results were independently checked. No native execution, full coercion matrix or broader client certification is asserted.