Hi L.Gerard,
Was it working fine before? On which application are you trying this?
You may press the F lock toggle key on the keyboard and then try F12 key for date stamp.
You may want to know:
Use “F5 key” to insert date stamp on notepad.
Alt+Shift+D to insert date stamp on word.
Thanks and Regards:
Ajay K
Microsoft Answers Support Engineer
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