You are configuring Azure File Sync. You have a cloud endpoint that has a file File1.txt. You have a server endpoint that also has a file File1.txt. What happens when you add the endpoints to the Azure File Sync Group?

If the files were changed in both endpoints, the newer file will keep its original file name and the older file will be renamed.

Azure File Sync uses a simple conflict-resolution strategy: Azure keeps both changes to files that are changed in two endpoints at the same time. The most recently written change keeps the original file name. The older file (determined by LastWriteTime) has the endpoint name and the conflict number appended to the filename. For server endpoints, the endpoint name is the name of the server. For cloud endpoints, the endpoint name is Cloud. The name follows this taxonomy:

{FileNameWithoutExtension}-{endpointName}-{#}.{ext}