Hello,
This error may occur if the previous temporary Open File Option (OFO) cache file does not get deleted.
To resolve the issue reboot the system then try backup.
If same problem occurs then perform following.
From Backup Exec | Tools | Wizards | Advance Open File Option Wizard
Provide the Administrator User name and password.
In the "Static Volume location" -> give the drive path having sufficient free space (if possible use drive where paging file location is not configured)
Click Next -> Check "Have Backup Exec calculate the initial and maximum size of static volume"
Finish the installation.
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