Passport Essential creating lots of unknown files in the backup

My 500GB backup drive can not back up 128GB of data the C: (1TB) drive. The Western Digital backup drive seems to be building up lots of unknown files over time to the point that it is unable to back up 128GB of data (confirmed using Windows hard drive properties) from the computer hard drive (C:) to the Passport Essential 500GB backup drive. The past three backups have reported early termination due to lack of backup space. I maintain only 1.7GB of user data on the backup drive and the SmartWare program reports 4.1GB free space on the backup drive so the remainder of the space is being used by backup files.

The Backup tab of the WD SmartWare program reports backup data on the drive as

1.6GB Documents

0.054.7GB Mail

5.0GB Movies

14.7GB Music

13.9GB Other

9.4 GB Pictures and

451.7GB Additional Files

The Backup tab also shows 84.1GB of System files. The backup data is reported to be one copy of the system image and the remainder is back up user data. Over time as the backup program has complained about not having enough space available for backup I have decreased the number of prior backup versions retained to only one. I have confirmed that SmartWare reports maintaining only the most recent backup version of user data along with the system image.

The problem looks to be the 451.7GB Additional files. I’m sure the 84.1GB system image is part of it but I can’t figure out how to recover the remainder of the space. The backup drive reports only 2% fragmentation

I am using a Western Digital My Passport Essential 500 GB, External, 5400 RPM (WDBAAA5000ABL) Hard Drive. The backup drive is set to back up weekly and has been operating for about 3+ years. The only data that is kept on the backup drive are 1.7GB of user data; the WD backup software, including virtual CD drive; and the backup files created by the backup software.

The OS is Windows 7 Home Premium service pack 1


Try uninstalling WD Smartware and reinstalling its latest version.