000856: An error was encountered while executing <value>.
Description
There are several possible causes for this error, investigate different possibilities.
Solution
Do the following:
Confirm that the syntax is correct, the input datasets exist as specified and are valid, and that write access to the output location is available.
Ensure that the machine has sufficient resources to complete the process.
Review the documentation for any notes or usage tips that may apply.
Contact Esri Technical Support if the problem persists.