To remove the any unwanted file(s) from the Mozy backup, simply deselect the file(s) from the MozyHome settings and run a backup. Because Mozy only backs up what you've selected, the next backup will mark those files for deletion and that will free up the space taken by those files.
To de-select files, Open Mozy settings> Click on File System tab> find the archive files you want to remove and remove the check marks next to them. Once you un-check them you should see the total usage change at the bottom of the settings window. Click OK to save the changes and start a backup. Once the backup is completed check your account for total space used.
Let us know if you have any questions.
If a response has resolved your issue please mark it as a solution to help the Mozy community.