How do I ensure data is entered as mm:ss.000

[slam]

I have the cell format set this way, but of course you can still enter anything.

I assume that data validation is the way to ensure the correct entry? How do I set that up? Looks like I need it to be set to custom, but what do I put in the formula box?

Thanks

 

[DonkeyOte]

Your format implies entries must always be less than 1 hour in which case you might specify Time validation where Min is 0 and Max is 0:59:59.999

 

[slam]

Your format implies entries must always be less than 1 hour in which case you might specify Time validation where Min is 0 and Max is 0:59:59.999

Excellent, that'll work!