Available with Network Analyst license.
Network dataset has VB or Python script evaluators or uses the Global Turn Delay evaluator. Script evaluators aren't supported in runtime.
Solution
Remove or replace the script evaluator or Global Turn Delay evaluator with another evaluator.
More information
Open the Network Dataset Properties dialog box, click the Attributes tab, choose the attribute that uses a script evaluator or Global Turn Delay evaluator, and remove the attribute entirely or change it to use a field, function, constant, or edge traffic evaluator rather than a script evaluator.