Invalid Drive Number

To UP a drive will not resolve MISSING PATH.

Use tpconfig on media server test.com to delete the drives with MISSING_PATH and rerun device wizard.

Which drive type are you using (scan command will list drive type and firmware)?

Also double-check tape driver. If IBM, note the following in HCL regarding IBM tape drivers:

If using the IBM Windows Tape Device Drivers be sure to choose the install_nonexclusive.exe executable. This option permits a tape drive to be accessed by multiple processes on a Media Server, which is a requirement for NetBackup.
NetBackup requires the IBM Data Path Failover feature to be disabled on the IBM tape device driver. To disable this feature, open the reg folder of the IBM driver
package, double-click DisableDPF.reg, and reboot the system.
- IBMTape driver level 6.2.1.7 tested on Windows

Please also ensure that Persistent Binding is done at HBA level.

Which Windows and NBU version on this media server?