In this case, it seems that the backup file has been corrupted; you may perform a manual restore from the following steps:
1- If your backup is stored on CD/DVD, copy the backup file to a local hard disk location. If you got an error message telling you that the data can't be copied, then you might need to use a CD/DVD data recovery utility such as ISObuster (shareware)
2- If your backup files were backed up in EXE format, then extract the .gbp file by going to "Tools" in the menu bar then choosing "Extract Archive from EXE file"
3- Genie Backup Manager uses Zip format to backup your data, so you can use any compression utility that supports zip (such as 7zip - freeware) to open the file, by renaming the .gbp extension to .zip.
4- After opening the renamed file, extract its contents to a temp location of your choice. Now you have all your data, but you need to restore it manually.
5- If you still couldn't open the file, then:
If you had your backup data spanned over multiple disks, you can repeat the same process with the sequentially numbered files (*.C000, *.C001, *.C002 etc ...) renaming each file to (.zip)