Veeam Backup & Replication – Cannot use tape Tape 1: unknown media (possibly in use by another application)

One of my tape jobs in Veeam Backup & Replication has failed with the following error:

Cannot use tape Tape 1: unknown media (possibly in use by another application)

The tape in the drive was previously used by Symantec BackupExec.  To use this tape in Veeam Backup & Replication it must be erased:

1. In the Veeam Backup & Replication console open the Tape Infrastructure view
2. Locate the tape under Tape Infrastructure -> Media Pools
3. Right-click the tape and choose Erase Tape
4. Select Short erase (fast) and click OK
5. Once the job has completed click OK
6. Run the backup job

The job should then find the free tape and use it.