I'm running into the same problem. Both feature services I'm using have under the 1,000 feature maximum. I'm only looking for one nearby feature per feature, so I'm definitely under the 100 maximum for number of nearest locations. I have network analysis privilege. When I filtered for only one feature and ran the tool to find its nearby feature, it ran smoothly. Now, when I try running the tool on all 900+ features, I receive an Error message saying "Error Find Nearest Failed."
Here are the parameters I'm setting for the tool:
1. Selected Feature Service of starting point features
2. Selected Feature Services of potential nearest locations (point features)
3. Drive Time
Use traffic Enabled
Traffic based on typical conditions for Monday 12:00 PM
4. For each location in the input layer
Limit the number of nearest locations to: 1 Enabled
Limit the search range to Disabled (Also tried enabling this and still received Error message)
5. Layer name provided
Include route layer Disabled
Use current map extent Disabled
Please help.