Netvault - Failed to Open file exclusions file

I using Netvault Backup to backup my database.
The Netvault backup has an option where we can exclude file with certain extention

I add a file with extention list want to exclude in backup

When Netvault start backup, it give this message :
Backup completed with warnings

I check Netvault log and found this
A problem occurred initializing items to exclude from the backup: "Failed to open file exclusions file 'c:\file\exclude.txt"


A problem occurred initializing items to exclude from the backup: "File exclusions file 'c:\file\exclude.txt" is not a valid Unicode file

Solve with :
Open and save exclude.txt as unicode file and backup successful without warning