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Unfortunately Matshita / Matsushita / Panasonic Drives are VERY problematic Drives and many owners are fully disappointed with the performance of these Drives.
These Drives are extremely Media â€˜PICKYâ€™ and require the use of top of the line known proven quality Media to perform effectively. Using run of the mill average quality Media only causes serious problems.
Suggest only using top of the line known proven quality Media that consistently produces quality error free results such as Taiyo Yuden or Verbatim Media. Using anything other than top of the line known proven quality Media WILL cause problems.
Also it is imperative to ensure that your Matsushita UJ850D Drive always has the newest most current up to date Firmware that is available installed on your Drive. Just because your NEC Versa LapTop is â€˜Newâ€™ is no guarantee that the Matsushita UJ850D Drive has the newest most current up to date Firmware that is available installed. Suggest visiting the Official NEC Web Site for your NEC Versa LapTop and ensure your Matsushita UJ850D Drive Firmware is up to date.