Since the version 2.4 I have this problem after run a model in ArcGIS Pro, I been looking for answers about I cant find it. Anybody knows a real BUG about it. Or a workaround that works.
ERROR:
Failed to execute. Parameters are not valid.
ERROR002851: Output %scratchGDB%\GridTemporal exists within geodatabase as C:\Users\rmesen\Documents\ROGER\ArcGIS\Projects\Revisión MAT\scratch.gdb\GridTemporal
Do you have your Environment parameters set to overwriteOutput?
From the internals - this is what I've been able to find -"Changed the output name for the feature class and looked for the duplicate name of the initial output name within the database and made sure to remove it since it did not contain any features in it." Hope this helps!