Drive says it is full, but it is not

I recently bought a new 3Tb MyBook drive for use as a backup drive. Installed the backup software, which initially seemed to work fine. A few days later, I got an error message that files could not back up because there is no room left on the drive. In File Explorer, it shows only 16Mb of free space, but the contents of the folders only comes to about 500Gb.
In fact, the C drive it is backing up only has 254Gb of used space.
How do I resolve thisÉ

Sorry ect…a full backup 3Tb drive is no fun…I’ve previously posted on this link: 1 TB Storage Amount is Not Correct

  • when you originally set up your schedule, you may have asked for the whole C: drive, or folders that mimic the whole drive.
  • my suggestion is to download a Free version of Treesize…a disk folder/file evaluator. After you run this, takes a few min with a progress bar on the bottom, you can view a Tree structure that shows all the folders/files on the backup drive. You can also expand each branch and drill down to expand. You can sort using Size or Files. For me, I used this program to uncover Millions of cache2 pointers from a Mozilla AppData/Local directory. Ended up Explorer deleting millions.
  • I ended up changing my backup files to exclude much of the access stuff being backed up. I realized that ultimately, my work, home, play, bookmarks and a few other files are most important. If I crash, I want my stuff available.
  • so, first you must find out whats on your storage, and also on your C: drives…then you can go forward. The History folder is the previous backups, and the Volume contain the current online files/folder.
  • here is a portion of my Passport, WD Backup.swstor folder with Treesize. Not too big now.


Hope you find you large file/folder location.

Thanks very much for this. I’ll give it a try, see what I learn.