ERROR999999 Region group tool

[AnnahNdeketeya]

i keep getting the following error when trying to run the region group tool. Can someone assist please.

ERROR 999999: Error executing function.
The table was not found. [VAT_name]
A column was specified that does not exist.
A column was specified that does not exist.
ERROR 010005: Unable to allocate memory.
ERROR 010067: Error in executing grid expression.
Failed to execute (RegionGroup).

[NeilAyres]

Some more info would be helpful, ArcGIS version, etc etc.

What is the grid expression that generates this error?

If by "grid" you are doing raster calculations as esri grid files, one thing could be spaces or other funny stuff in your path to the data.

[AnnahNdeketeya]

I'm using V 10.6. I'm not using arcpy but the tool as attached here so i don't know if your question about grid expression still applies. The input file is output from the boundary clean tool. The file is relatively large Sorry i'm not a GIS expert so might be getting you wrong. if so, please explain.

[NeilAyres]

If the raster is very large, you may be running into memory problems with the 32bit application. Even though you have much more physical memory than that, ArcMap can only access 4Gb. Can you try your workflow / tool in Pro? 64bit based, so memory should not be a problem.

[AnnahNdeketeya]

Thank you Neil. it worked with Pro. 

[DanPatterson_Retired]

Ensure it is and integer raster.

Better still, export the raster to a *.tif file using Copy Raster.  If that doesn't work, cut a chunk out (say 1/4) and use it to see if it is a file size issue.

[CarlosRibeiro]

It will fail if input raster is stored in FGDBR format (geodatabase), either executing Region Group in ArcMap/ArcCatalog 10.7.1 or ArcGIS Pro 2.4.

If input raster is stored in ESRI grid format (in a workspace), it wil run like a charm. It took ~118hr to identify ~20 million groups from a raster having 14,951x12,704 8bit cells...

This also works fine in ArcGIS Pro 2.4 if your input data is a TIFF image. However, the performance will be a bit slower (~120.5hr) .