Hello,
As you ahve mentioned here that you are getting this error while performing inventory operation, we want to know have nebled the bar code rule on the library?
If yes, then you cannot perform the inventory.
Note :we can not perform the inventory if the bar code rule is enabled on the library.It is required to activate the bar code rule on the libaray in the backup exec also.
1.clcik on the library and select the option "activate the bar code"
2.Refer the following technote
How to enable a bar code label rule and configure it for the tape device
http://support.veritas.com/docs/259444
3.Then initialize the library
4.Scan the slots in which media are present.
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