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Is this message acceptable to (by) you?

Sorry, I'm getting confused. I'm sure 'by' is wrong, but can you confirm, please?
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Hi,

You need to say 'to'.

However, you could say 'Is this message OK by you?'

Best wishes, Clive
Comments  
It is 'acceptable to sb' not 'by sb'
for example: is the proposal acceptable to you?