When running an inventory operation within a robotic library, the job fails with the following error and alert (Figure 1):
"0xA000821 - Library Error - incompatible storage media detected in robotic library:

Figure 1
 

Note: When a library has a bar code reader installed, media inventory usually does not have to take place. The only instance when a tape needs to be inventoried is if the tape does not exist inside the database, or the media is showing up as "Unknown Media," "Unrecognized Media," or "Bad Media." Sometimes, in these cases where the tapes are unrecognized, even an inventory will not show the proper label, and the tapes must be erased or formatted to work correctly. To see if the media is listed in the Backup Exec database, click Media on the navigation bar, click All Media in the left pane, and look for the tape label in the right pane. If the tape label exists, the tape does not need to be inventoried.

This error message occurs because the bar code rules have been enabled, but there are no rules set up for the media within the robotic library. Since there are no rules defined, Backup Exec is unable to find any media that is compatible with the tape drive inside the library.


Resolution:

If the robotic library does not have a bar code reader or bar code rules do not need to be used, perform the following:

1. Click Devices on the navigation bar.

2. Under Robotic Libraries, right-click the library and click Properties

3. Click the Configuration tab.

4. Clear the Enable Bar Code Rules check box.

5. Click OK

If the robotic library does have a bar code reader and bar code rules are to be used, a rule needs to be created for the library to work correctly. To do this, perform the following steps:

1. Click Tools | Options

2. In the left pane, click Bar Code Rules.

3. Click Add.

4. Select the Media Type that corresponds to the tape drive.

5. Type the name of the vendor of the tape drive in the Vendor box.

6. Type the bar code prefix in the Barcode Prefix box and the bar code suffix in the Barcode Suffix box. Typing just a bar code prefix or a bar code suffix is fine. Typing both the bar code prefix and the bar code suffix is also fine.

7. Click OK.

8. If any more rules need to be added, click Add again.

9. Once all rules have been added, click OK until all dialog boxes are closed.


However, if this error occurs on a Standalone Tape drive, please refer to the below mentioned technote to troubleshoot the issue:

Title:  How to troubleshoot issues with a Robotic Library or Tape Drive in Backup Exec for Windows Servers.
http://support.veritas.com/docs/255501

Note: Please consult Symantec Technical Support before performing the steps mentioned in Point VI and VII from this technote.