# CannotTrackChange Event

> Occurs when a document change cannot be tracked, such as deleting a table column or merging cells; Cancel and Handled replace the default message box.

- **Product:** TX Text Control ActiveX
- **Section:** Documentation
- **Kind:** Event
- **Path:** TX Text Control ActiveX > API Reference > TXTextControl > CannotTrackChange Event
- **263 words**
- **Web URL:** https://docs.textcontrol.com/tx-text-control-activex/reference/txtextcontrol/cannottrackchange-event/
- **LLMs URL:** https://docs.textcontrol.com/tx-text-control-activex/reference/txtextcontrol/cannottrackchange-event/llms.txt
- **LLMs-Full URL:** https://docs.textcontrol.com/tx-text-control-activex/reference/txtextcontrol/cannottrackchange-event/llms-full.txt

---

Determines how to handle a change of the document that cannot be added to the list of tracked changes. Complex table layout changes, such as deleting a table column or merging table cells cannot be tracked. The default handling shows a MessageBox asking the end-user whether the change of the document should be performed. Using the event parameters the default handling can be changed.

Introduced: 26.0.

### Syntax

```vbscript
CannotTrackChange(Cancel, Handled)
```

### Parameters

| Parameter | Description |
|---|---|
| Cancel | When this parameter is set to true, which is the default value, the operation is canceled. When this parameter is set to false, the document is changed. |
| Handled | A subscriber can set this parameter to true to indicate that he has handled the event. In this case the default handling is suppressed. The default handling shows a MessageBox asking the end-user whether the change of the document should be performed. |

### Data Types

| Name | Data type |
|---|---|
| Cancel | Boolean |
| Handled | Boolean |

### See Also

- [Programming Category: Tracking Document Changes](https://docs.textcontrol.com/tx-text-control-activex/reference/categories/track-changes/llms-full.txt)

---

## Nearby

- **Previous:** [CanEdit Property](https://docs.textcontrol.com/tx-text-control-activex/reference/txtextcontrol/canedit-property/llms-full.txt)
- **Next:** [CanParagraphFormat Property](https://docs.textcontrol.com/tx-text-control-activex/reference/txtextcontrol/canparagraphformat-property/llms-full.txt)