## TL;DR
Fix this in the SIG importer by acting on the exact message first: open the workbook, copy the answers onto the worksheet whose name matches the SIG template sheet name for that SIG version, delete extra worksheets, and re-import the single-sheet workbook. Do not rerun the whole job unchanged, because the same inputs produce the same failure. Prove the fix on one item, then rerun the full scope and reconcile the counts.

```text
invalid worksheet
```

## Use this when
- The operation in the SIG importer fails with this exact message: invalid worksheet.
- The same failure repeats on retry with unchanged inputs.
- A review, export or check is blocked until this item completes.

## Not for this skill when
- The message is a permission or outage notice from the platform. Resolve that first, then return here if this error remains.
- The operation completes and you only disagree with its output. That is a quality review, not this failure.

## Steps
1. Reproduce the failure with the smallest scope that still shows it in the SIG importer, and copy the full message plus the questionnaire, answer or evidence item involved into the run notes. Verify: the error is reproduced on demand with a named item, not only seen in a log.
2. Apply the specific fix for this error: open the workbook, copy the answers onto the worksheet whose name matches the SIG template sheet name for that SIG version, delete extra worksheets, and re-import the single-sheet workbook. Verify: the import log names the expected worksheet and reports the full question count with no invalid worksheet message.
3. Check the neighbouring items that share the same config, template, feed or credential, because this class of failure rarely affects only one item. Verify: the neighbouring items are listed and each is marked affected or clear.
4. Compare the result counts, decisions or alerts against the source in the SIG importer so a silent partial success is caught before sign off. Verify: counts match the source or every difference is named and explained.
5. Rerun the original operation in the SIG importer on the previously failing scope, watching for the same message rather than assuming success from a quiet log. Verify: the operation completes and the original message does not appear.
6. Record the fix, the triggering input and the verification result on the item so the next occurrence is recognised immediately. Verify: the record names the error, the fix applied and the evidence of success.

## Why it happens
the importer selects its worksheet by exact name, so a renamed, reordered or customer-branded sheet reads as invalid even when the answers are fine.

## Variant phrasings

### invalid worksheet
The verbatim form searchers paste from the terminal or console. Treat it identically: same fix, same single item proof, then the full rerun.

### How to fix: SIG questionnaire import error "invalid worksheet" vendor assessment broken failure
The how-to phrasing for the same failure in the SIG importer. The steps above apply unchanged; start at the reproduction step rather than skipping to the rerun.

### the SIG importer troubleshooting for this failure
The symptom-first phrasing used when the console hides the full message. Surface the full message first, confirm it matches the code block above, then follow the steps.

Compatibility: the SIG importer at current versions, plus the platform API or console the query names; no extra tooling beyond a text editor and the source system access needed to verify counts.

## Provenance

Resolved from the public thread: https://vectle.com/posts/pst_w-RIHXU8U5q7g-n-4QQqWQ