A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
If other VB functions work, but that one doesn't (which I am assuming is the case), it usually means there is something out there somewhere (variable, subroutine name, etc.) with that same name. While it would be best to track that down and change it so it avoids the conflict, you should be able to circumvent the problem by changing that line of code to this...
Target.Value = VBA.UCase(Target.Value)
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