On many modern Windows apps and configurations, the Insert key is disabled or not assigned to any action by default, so pressing it appears to “do nothing,” even though the key itself is working.
If the issue is specifically that text is being overwritten instead of inserted (or vice versa) in Word, that is controlled by “Overtype mode,” not by hardware:
- Open Word.
- Select File > Options.
- Select Advanced.
- Under Editing options, clear both:
- Use the Insert key to control overtype mode
- Use overtype mode
This forces Word to always insert text instead of toggling to overtype with the Insert key.
If the Insert key truly does nothing anywhere (including in apps that support it) even with multiple keyboards, then the behavior is application- or OS-level rather than a keyboard hardware fault.
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