ERROR 999999 appearing when I try to Classify Objects Using Deep Learning

[ScarletMaguire]

I am trying to classify a set of 160 polygons into categories using a pre-trained Deep Learning model, with the "Classify Objects Using Deep Learning" tool. However I keep getting this message:  

"ERROR 999999: Something unexpected caused the tool to fail. Contact Esri Technical Support (http://esriurl.com/support) to Report a Bug, and refer to the error help for potential solutions or workarounds. "

These are the things I have tried/checked:

• I have Repaired Geometry, so none of my polygon overlap.
• I have checked that my input raster and all polygons in my input layer overlap i.e. all of my polygons have raster information filling the whole polygon
• My input raster and polygon layer are using the same coordinate system
• My output file has been given an appropriate alphanumeric name i.e. no symbols

If anyone can suggest where i may be going wrong, that would be great. Thank you in advance.

[DanPatterson]

There are a number of Related links to the right of your question, eg

Solved: Classify Objects Using Deep Learning - Unexpected ... - Esri Community

have your explored those posts?

[PavanYadav]

@ScarletMaguire Can you share some more info e.g. ?

1. pre-trained model name (or link)

2. version of ArcGIS Pro. 

optionally, a screen capture of the tool or command 

Please make sure you're using a model that is built for Object Classification.