A buffer I created successfully executed, but I received the following message: "WARNING 000632: Datum conflict between map and output." How can I fix this?
This isn't really a big deal, just a minor warning from ArcGIS. If you want it to go away, change the spatial reference for your data frame to match that of your output feature class. More info: 000632 : Datum conflict between map and output.
Docs on how to change your data frame's spatial reference: Specifying a coordinate system