Deleting old tape backups from VBR ?

​@Stabz You can follow the procedure from this URL: https://helpcenter.veeam.com/docs/vbr/userguide/moving_tapes_to_custom_pool.html?ver=13

I think it will help you

When you say the tapes are unavailable do you mean they just aren’t physically available to you, but their still in the media pools? You will need to go to the Tape Infrastructure, find the tape server or library, open the Media folder, right click on the tape those backup are on, then click “Remove from Catalog”.

You can see more about that here: https://helpcenter.veeam.com/docs/vbr/userguide/removing_tapes_from_catalog.html?ver=13

There are not presents in any mediapool and also not physically available 😆
 

Then a support case to have them help you clean up the DB is probably the way forward.

Yep let’s go for a new one 

Even if they are in the library you can’t delete them from there. 

You’ll want to go under Tape Infrastructure.

From there you can select a media pool with the tapes you are talking about.  

You can Erase tapes and mark them as free. I always recommend a quick erase to not have Veeam want to scan them and import them if the database ever gets restored as it can take a LONG time and it finds many very old backups. 

Erasing Tapes - Veeam Backup & Replication User Guide

In your case, the tapes might be showing as offline or in a vault as they are not in the library you said. If they are configured as Protected, you will have to turn that off first. 

Removing Tapes from Catalog - Veeam Backup & Replication User Guide

If you are feeling brave, you can remove tapes and data written from the catalog and DB, I recommend support first or the first time you use this or try in a lab.

Remove-VBRTapeMedium - Veeam Backup & Replication Veeam PowerShell Reference