Checkbox no longer available

The availability of the new in-cell checkbox feature in Excel 2024 depends on your update channel and build version. Initially, this feature was introduced to users in the Beta Channel (Insider version). As of July 26, 2024, reports indicate that it became available in the Current Channel of Microsoft 365.

Microsoft has introduced a new built-in checkbox feature that behaves differently from older Form Controls and ActiveX checkboxes.

I haven't looked into Excel 2024 that much but here are some Possible Causes of Your Issue.

1. You used Form Controls or ActiveX Checkboxes

• If these were removed, the linked cells still show TRUE/FALSE, but the checkboxes disappear.

2. Your Excel updated to the new checkbox feature

• Microsoft recently added a "Checkbox" option under Insert, replacing older checkbox methods.
• This could have affected how checkboxes display in your file.

Solution

Check if the New Checkbox Feature is Available

• Select a cell where you want a checkbox.
• Go to Insert > Checkbox (under "Cell Controls").
• If this option is missing, your Excel version might not have the latest update yet.

Recover Form Controls Checkboxes

1. Enable Developer Tab

• Go to File > Options > Customize Ribbon
• Check Developer and click OK
• Go to Developer > Insert > Form Controls > Checkbox

2. Check if Controls Are Disabled

• Go to File > Options > Add-ins
• At the bottom, choose Disabled Items and click Go
• If you see anything related to Form Controls, enable it.

Try Converting the File Format

• If the file is in .xls format, save it as .xlsx and reopen it.

My answers are voluntary and without guarantee!

Hope this will help you.