If any of you looking for a solution to deal with your corrupted BKF file, I'll suggest you to get a third-party BKF recovery tool. As there's no manual way to fix or repair corrupted BKF file, you have to go for a third-party tool. Though it could be little tricky for you to select the right tool as there are many software companies in the market which are providing commercialware tools for such purpose. If you are looking for a recommendation, then I would like to recommend you SysInfoTools Backup Exec BKF Repair tool here. It can recover easily recover your data from corrupted BKF files. I haven't tried it, but came to know about it through a blog. In that blog, I read about the corruption in BKF file, why a BKF file gets corrupted, etc. You can also read this blog: Letís Find Out How to Repair BKF File Ė Professional BKF Recovery | N. Sem's Blog.
Thanks and best regards.