Backup freeze @ worktkt.dat

Hello everyone,

I am facing problem while doing backup. Backup  gets freeze when it reaches WORKTKT.DAT file. I waited for 2 hours but backup percentage did not start then I cancelled the backup and once again I started the backup company process eventhen it freeze at WORKTKT.DAT. Since one month I didnt able to backup the company files. Please, help me to fix the problem?