How do I remove a specific file or folder from my backup?

Delete backup set and files
You can delete a backup set if it is no longer needed. You cannot delete a backup set if only one backup set is available. However, you can create a new backup set before you delete the old backup set.

Sometimes, a back-end service outage or server maintenance can stop you from deleting your backup data. In such cases, try deleting after some time. To identify if there is a service outage, check the Norton Service Status page.

When a backup set is deleted, the Backup details of the files that are included in that backup set also change. For example, the icon overlays and the Backup tab in the file properties of the file no longer appear.

Delete backup set and files from Cloud Backup ›
Delete backup set and file from local backup ›
VIDEO: HOW TO DELETE A BACKUP SET AND THE FILES THAT YOU BACKED UP

https://support.norton.com/sp/en/us/home/current/solutions/v19828921 

Manage backup files on Norton Backup Drive
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VIEW BACKUP FILES ON THE NORTON BACKUP DRIVE
In Windows Explorer, click Norton Backup Drive.

Select the backup destination and navigate to the backup set that contains the files that you backed up.

RESTORE A FILE FROM A BACKUP SET ON THE NORTON BACKUP DRIVE
In Windows Explorer, click Norton Backup Drive.

Select the backup destination, and navigate to the backup set destination that contains the file that you backed up.

Do one of the following:

Right-click to select the files to restore in Norton Backup Drive, and then click Restore. The files are restored to the original location by overwriting the existing files.

Right-click to select the files to restore in the Norton Backup Drive, and then click Restore to. You can choose to restore your files to the Original Location or to a New Location.

DELETE A FILE FROM A BACKUP SET ON THE NORTON BACKUP DRIVE
In Windows Explorer, click Norton Backup Drive.

Select the backup destination, and navigate to the backup set destination that contains the file that you backed up.

Do one of the following:

• Right-click to select the files to delete, and then click Delete.
• Select the file, and then click Delete.

https://support.norton.com/sp/en/us/home/current/solutions/v19828933 

Hi I am trying to work out a way to view my backups and identify specific folders or files that I no longer need to keep in my backup.

Listings on what is in your backup set are not too easy to find or use.

1. Just using the backup feature in 360 to preview the files in a backup set will just give you a very long list of the files with no way to sort through them.
2. If you use the method of viewing the backup sets from your Norton Account, that will give you a better way to view the backup set contents to help you identify the files/folders you wish to remove. But that only allows you to download the files.
3. Using the Norton Backup Drive in Windows Explorer will allow you to remove the files from the online storage, but it will not remove it from the backup set. 

What you can do with #2 and #3 is open a separate instance of Windows Explorer. Using the information on the files/folders you identified for removal from the backup set, locate those items and right click on them and click on Norton 360 > Exclude from Backup.

Then, unfortunately, it seems you are stuck scrolling through the list from the backup preview. That, or do as bjm_ suggested above and just start a new backup set.

Apparently not. I just did a test backup to a network drive and it does show up in the Norton Backup Drive. You just need to ensure that your destination drive is mapped to a drive letter in Windows Explorer.

So you should be able to browse your folders and files in the Norton Backup Drive, and then open another Windows Explorer instance and use the right click to remove the folder/file from the backup. Be sure you are going to the original folder/file location in Explorer. Not the listing in Norton Backup Drive.

You appear to be looking in your backup on the NAS. That is going to be encrypted. You need to look at the files on your computer that are being backed up.

To delete the files from your external drive, you use the method above to browse through your backup set using Windows Explorer and the Norton Backup Drive. Navigate through your backup there and when you find folders or files you want to delete, right click on them and click on Delete.

If you are looking at the NAS drive letter, then no. You cannot see the backup contents. You need to use the Norton Backup Drive that you find when you click on This PC, and look in the right pane for Norton Backup Drive and double click that.

Then you look for the backup set that is stored on your NAS and double click on that.

Then start navigating through your backup set to the folders or files you want to delete.

My example is a test where I saved the backup to a network drive I have that I mapped the destination folder to drive letter N:

Hi Davot10, It's often not recommended to delete files that are inside your backups. But I understand that you're forced to do so in this instance because you want to control the space your backup occupies on your NAS. You asked, "I'm seriously considering whether Norton is the best solution for me based on this and what it costs. Never mind the constant upselling." From what I read, you seem to WANT to be able to control what files and folders get backed up and the space your backup occupies on your NAS. While Norton allows you to configure WHAT files, WHERE to backup and WHEN to backup, problem is - it's missing what I think you WANT - a functionality called "backup retention policy". Try googling the term if you like. Please feel free to skip the rest of the post if I've misunderstood your requirement(s). In simplest terms, it's how long a copy of files and folders (taken by a backup today) will live on your NAS and be available for your to restore. It's often configured in days i.e. 60 days or 180 days. You can imagine this functionality putting an "expiry date" on copies of your backups in your NAS. After that expiry date, the backup software automatically free up and recycle the space. No more manual intervention! :-) It's a systemic process that lets users adjust and control the space occupied by your backups because our NASes do not have 'infinity' space. There are other ways... but this is often 'good enuf'. Suggestion: Check if your NAS has a free backup utility that supports "backup retention". P.S. Sorry, I can't help with constant upselling :-)