The incremental backup that runs after this error, "The software trial period has expired", gets promoted to a full backup when a license is applied.

Problem

The incremental backup that runs after this error, "The software trial period has expired", gets promoted to a full backup when a license is applied.

Error Message

Exception in Job Log : 
Resource \\servername\C: was not found in the previous instance of this job. It will be fully protected in this job.

Cause
 

The software license should be renewed before the current license expires. It is important because the backups continue to run as normal, backing up the workload without a miss to create a recovery point.

Solution

Install the renewed license before the current one expires.