Use Date & " " & Time. Ampersands are for concatenation in VBA. You can sometimes get away with "+", but it's better to do it correctly all the time, rather than get used to a way that sometimes works and somwtimes gives unexpected results.
Also, sheet names are limited to 31 characters, and some characters are disallowed in worksheet names, including: \ / * [ ]
It's also a good idea to avoid allowed characters that will cause confusion, such as ' " ! + - &
I stick with letters, numbers, spaces, and the underscore character.
Jon Peltier, Microsoft Excel MVP
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