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[Tristram_ZX81]

The image below has the same formula in Column F3 down to F1000 as the second image. I can't figure out why it's not populating row F with data in the first image! Any ideas?

 

[Cubist]

The 0's suggest that the formula couldn't find any row matching the conditions. Check if column J on 'MS Data' is date/time data type and not text.

 

[Tristram_ZX81]

Thanks Cubist. I've tried switching Column J on the LMS Data tab between text and general in Text to Columns, and also formatted it into the various 24 hour clock options, but I'm still getting zero on my TC Required tab. Any ideas?