Hello,
This error could occur if the "Enable Agents Using AppleTalk Protocol" is checked from Tools > Options > AppleTalk of Backup Exec, and the AppleTalk
protocol is not available or disabled.
If the Backup Exec server is not communicating with any Macintosh computers then the option "Enable Agents Using AppleTalk Protocol" should be deselected.
If the AppleTalk protocol was removed or disabled, Backup Exec setting needs to be refreshed. Go to Tools > Options > AppleTalk, and it will be shown deselected. Click OK to save settings.
Note: It may take more time than normal to open Tools > Options >AppleTalk tab.
Thanks,
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