Error 999999 when using Classify Objects Using Deep Learning

[ScarletMaguire]

I am trying to run the Classify Objects Using Deep Learning tool but the 999999 error keeps appearing, along with some other messages (see in screenshots below). I have ran this same model before with no problems and I have even tried re-running it with previous input features that have worked in the past.

If anyone has any suggestions on what may be causing this, it would be greatly appreciated.

[RTPL_AU]

@ScarletMaguire 
More often than not that error is caused by something in a dataset name or path such as too many characters in the path (those DEEP project management generated network paths...) or funny characters ($%&* etc) in a name.
Depending on what you're doing it may be that there is something in a field name, attribute, etc - especially if it isn't an Esri native file (CSV, Excel).

It is a bit of a catch-all error that can be caused by many other things too but checking your names & paths is a good start. 
It may take copying stuff to a local drive with short names to rule it out.

[DanPatterson]

apparently you have run into this issue before

ERROR 999999 appearing when I try to Classify Obje... - Esri Community

perhaps you can share the information requested in that post or how you resolved that previous situation/.

[ScarletMaguire]

Hi, yes I did run into a similar issue a while back, but this time the error codes are completely different, and I am not able to resolve the issue using the same means as last time.

But thank you for the advice, I will keep looking at ways of troubleshooting.

[RichardDaniels]

As a start I would check the shapefile location you are trying to create or save results to. Is it on your local machine (NOT in OneDrive), Do you have full r/w/modify permissions to the folder, Is the folder path 'shallow' (e.g., C:\Temp\Results\myshape file), I would also consider saving the results to a file geodatabase vs. a shapefile. Last, if you are saving datetime fields recall that a new datetime format was introduce with Pro 3.4 that is not supported in shapefiles.