Hello,
Please note that generally this error may occur when Use Advanced Open File Option is selected in the backup job properties, however the Advanced Open File Option (AOFO) is either not licensed within the product, or the target system does not have the AOFO software installed.
As you have mentioned here that you ared not using AOFO, perform the following steps:
1.Create a small backup job
2. and select Open file backup when Advance open file option is not used to "NEVER"
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