Windows 7: Cannot Delete Old System Restore Entries

I have searched around the web and there doesn't seem to be any answers to this issue.

When opening System Restore, there are a whole bunch of old entries. I cannot remove them, and even deleting all other shadow copies doesn't affect them. When trying to restore from them, an error message shows up.

It appears these restore points do not actually exist anymore and are just references to old points. Is there anyway I can delete them from the list??

Thanks

It's a problem with your backups. There is a catalog showing that those backups exist, yet the drive they are on is either disconnected or the backups have been improperly deleted from the drive. The restore points marked "backup" are not standard restore points.

Even after disconnecting the backup drive, these restore points are still shown. How can I remove them? Will reformatting the backup drive help?

Go into the backup system and delete the old backups.

Don't know if this any use in this case, but CCleaner will remove old System Restore Points.

I have tried CCleaner, the restore points to not even appear there!
They seem as though they are not even treated as regular restore points (clearing all other restore points leaves these in tact).

I have only made backups on one computer, the one I am using now, and I have found no way to delete these redundant entries.